Hey Avidal,

Use this i have removed the sidebar code . 

<!--?php get_header(); ?-->
<!--?php 
global $nectar_theme_skin, $options;
$bg = get_post_meta($post--->ID, '_nectar_header_bg', true);
$bg_color = get_post_meta($post->ID, '_nectar_header_bg_color', true);
$fullscreen_header = (!empty($options['blog_header_type']) && $options['blog_header_type'] == 'fullscreen' && is_singular('post')) ? true : false;
$blog_header_type = (!empty($options['blog_header_type'])) ? $options['blog_header_type'] : 'default';
$fullscreen_class = ($fullscreen_header == true) ? "fullscreen-header full-width-content" : null;
$theme_skin = (!empty($options['theme-skin']) && $options['theme-skin'] == 'ascend') ? 'ascend' : 'default';
$hide_sidebar = (!empty($options['blog_hide_sidebar'])) ? $options['blog_hide_sidebar'] : '0'; 
$blog_type = $options['blog_type']; 
$blog_social_style = (!empty($options['blog_social_style'])) ? $options['blog_social_style'] : 'default';
if(have_posts()) : while(have_posts()) : the_post();
    nectar_page_header($post->ID); 
endwhile; endif;
 if($fullscreen_header == true) { 
    if(empty($bg) && empty($bg_color)) { ?>
        <div class="not-loaded default-blog-title fullscreen-header" id="page-header-bg" data-midnight="light" data-alignment="center" data-parallax="0" data-height="450" style="height: 450px;">
            <div class="container">    
                <div class="row">
                    <div class="col span_6 section-title blog-title">
                        <h1 class="entry-title"><!--?php the_title(); ?--></h1>
                        <div class="author-section">
                             <span class="meta-author">  
                                 <!--?php if (function_exists('get_avatar')) { echo get_avatar( get_the_author_meta('email'), 100 ); }?-->
                             </span> 
                             <div class="avatar-post-info vcard author">
                                 <span class="fn"><!--?php the_author_posts_link(); ?--></span>
                                 <span class="meta-date date updated"><i><!--?php echo get_the_date(); ?--></i></span>
                             </div>
                        </div>
                    </div>
                </div>
            </div>
            <!--?php 
                  $button_styling = (!empty($options['button-styling'])) ? $options['button-styling'] : 'default'; 
                  if($button_styling == 'default'){
                      echo '<div class="scroll-down-wrap"--><a href="#" class="section-down-arrow"><i class="icon-salient-down-arrow icon-default-style"> </i></a></div>';
                  } else if($button_styling == 'slightly_rounded' || $button_styling == 'slightly_rounded_shadow') {
                      echo '<div class="scroll-down-wrap no-border"><a href="#" class="section-down-arrow"><svg class="nectar-scroll-icon" viewBox="0 0 30 45" enable-background="new 0 0 30 45">
                            <path class="nectar-scroll-icon-path" fill="none" stroke="#ffffff" stroke-width="2" stroke-miterlimit="10" d="M15,1.118c12.352,0,13.967,12.88,13.967,12.88v18.76  c0,0-1.514,11.204-13.967,11.204S0.931,32.966,0.931,32.966V14.05C0.931,14.05,2.648,1.118,15,1.118z"></path>
                          </svg></a></div>';
                  } else {
                      echo '<div class="scroll-down-wrap"><a href="#" class="section-down-arrow"><i class="fa fa-angle-down top"></i><i class="fa fa-angle-down"></i></a></div>';
                  }
            ?>
        
    <!--?php } 
    if($theme_skin != 'ascend') { ?-->
        <div class="container">
            <div id="single-below-header" class="<?php echo $fullscreen_class; ?> custom-skip">
                <!--?php if($blog_social_style != 'fixed_bottom_right') { ?-->
                    <span class="meta-share-count"><i class="icon-default-style steadysets-icon-share"></i> <!--?php echo '<a href=""--><span class="share-count-total">0</span> <span class="plural">'. __('Shares',NECTAR_THEME_NAME) . '</span> <span class="singular">'. __('Share',NECTAR_THEME_NAME) .'</span> '; nectar_blog_social_sharing(); ?> </span>
                <!--?php } else { ?-->
                    <span class="meta-love"><span class="n-shortcode"> <!--?php echo nectar_love('return'); ?-->  </span></span>
                <!--?php } ?-->
                <span class="meta-category"><i class="icon-default-style steadysets-icon-book2"></i> <!--?php the_category(', '); ?--></span>
                <span class="meta-comment-count"><i class="icon-default-style steadysets-icon-chat-3"></i> <a href="<?php comments_link(); ?>"><!--?php comments_number( __('No Comments', NECTAR_THEME_NAME), __('One Comment ', NECTAR_THEME_NAME), __('% Comments', NECTAR_THEME_NAME) ); ?--></a></span>
            </div><!--/single-below-header-->
        </div>
    <!--?php }
 } ?-->
<div class="container-wrap <?php echo ($fullscreen_header == true) ? 'fullscreen-blog-header': null; ?> <?php if($blog_type == 'std-blog-fullwidth' || $hide_sidebar == '1') echo 'no-sidebar'; ?>">
    <div class="container main-content">
        
        <!--?php if(get_post_format() != 'quote' && get_post_format() != 'status' && get_post_format() != 'aside') { ?-->
            
            <!--?php if(have_posts()) : while(have_posts()) : the_post();
            
                if((empty($bg) && empty($bg_color)) && $fullscreen_header != true) { ?-->
                    <div class="row heading-title" data-header-style="<?php echo $blog_header_type; ?>">
                        <div class="col span_12 section-title blog-title">
                            <!--?php if($blog_header_type == 'default_minimal') { ?--> 
                            <span class="meta-category">
                                    <!--?php $categories = get_the_category();
                                            if ( ! empty( $categories ) ) {
                                                $output = null;
                                                foreach( $categories as $category ) {
                                                    $output .= '<a class="'.$category--->slug.'" href="' . esc_url( get_category_link( $category->term_id ) ) . '" alt="' . esc_attr( sprintf( __( 'View all posts in %s', NECTAR_THEME_NAME), $category->name ) ) . '">' . esc_html( $category->name ) . '';
                                                }
                                                echo trim( $output);
                                            } ?>
                                    </span> 
                             <!--?php } ?-->
                            <h1 class="entry-title"><!--?php the_title(); ?--></h1>
                            
                            <div id="single-below-header">
                                <span class="meta-author vcard author"><span class="fn"><!--?php echo __('By', NECTAR_THEME_NAME); ?--> <!--?php the_author_posts_link(); ?--></span></span><!--
                                  --><span class="meta-date date updated"><!--?php echo get_the_date(); ?--></span><!--
                                --><!--?php if($blog_header_type != 'default_minimal') { ?--><span class="meta-category"><!--?php the_category(', '); ?--></span> <!--?php } else { ?--><!--
                                    --><span class="meta-comment-count"><a href="<?php comments_link(); ?>"> <!--?php comments_number( __('No Comments', NECTAR_THEME_NAME), __('One Comment ', NECTAR_THEME_NAME), __('% Comments', NECTAR_THEME_NAME) ); ?--></a></span>
                                <!--?php } ?-->
                            <!--project-additional-->
                            </div><!--/single-below-header-->
                            
                            <!--?php if($blog_header_type != 'default_minimal') { ?-->
                                <div id="single-meta" data-sharing="<?php echo ( !empty($options['blog_social']) && $options['blog_social'] == 1 ) ? '1' : '0'; ?>">
                                    <ul>
                                        
                                        <li class="meta-comment-count">
                                            <a href="<?php comments_link(); ?>"><i class="icon-default-style steadysets-icon-chat"></i> <!--?php comments_number( __('No Comments', NECTAR_THEME_NAME), __('One Comment ', NECTAR_THEME_NAME), __('% Comments', NECTAR_THEME_NAME) ); ?--></a>
                                        </li>
                                        
                                         <li>
                                               <!--?php echo '<span class="n-shortcode"-->'.nectar_love('return').''; ?>
                                           </li>
                                        <!--?php if( !empty($options['blog_social']) && $options['blog_social'] == 1 &&  $blog_social_style != 'fixed_bottom_right') { 
                                               
                                                echo '<li class="meta-share-count"--><a href="#"><i class="icon-default-style steadysets-icon-share"></i><span class="share-count-total">0</span></a> <div class="nectar-social">';
                                               
                                            
                                                //facebook
                                                if(!empty($options['blog-facebook-sharing']) && $options['blog-facebook-sharing'] == 1) { 
                                                    echo "<a class="facebook-share nectar-sharing" href="#" title="".__(" share="" this',="" nectar_theme_name)."'=""> <i class="fa fa-facebook"></i> <span class="count"></span></a>";
                                                }
                                                //twitter
                                                if(!empty($options['blog-twitter-sharing']) && $options['blog-twitter-sharing'] == 1) {
                                                    echo "<a class="twitter-share nectar-sharing" href="#" title="".__(" tweet="" this',="" nectar_theme_name)."'=""> <i class="fa fa-twitter"></i> <span class="count"></span></a>";
                                                }
                                                //google plus
                                                if(!empty($options['blog-google-plus-sharing']) && $options['blog-google-plus-sharing'] == 1) {
                                                    echo "<a class="google-plus-share nectar-sharing-alt" href="#" title="".__(" share="" this',="" nectar_theme_name)."'=""> <i class="fa fa-google-plus"></i> <span class="count">0</span></a>";
                                                }
                                                
                                                //linkedIn
                                                if(!empty($options['blog-linkedin-sharing']) && $options['blog-linkedin-sharing'] == 1) {
                                                    echo "<a class="linkedin-share nectar-sharing" href="#" title="".__(" share="" this',="" nectar_theme_name)."'=""> <i class="fa fa-linkedin"></i> <span class="count"> </span></a>";
                                                }
                                                //pinterest
                                                if(!empty($options['blog-pinterest-sharing']) && $options['blog-pinterest-sharing'] == 1) {
                                                    echo "<a class="pinterest-share nectar-sharing" href="#" title="".__(" pin="" this',="" nectar_theme_name)."'=""> <i class="fa fa-pinterest"></i> <span class="count"></span></a>";
                                                }
                                                
                                              echo '</div>';
            
                                             }
                                        ?>
                                        
            
                                    </ul>
                                    
                                    
                                </div><!--/single-meta-->
                                <!--?php } ?-->
                        </div><!--/section-title-->
                    </div><!--/row-->
                
            <!--?php }
            
            endwhile; endif; ?-->
            
        <!--?php } ?-->
            
        <div class="row">
            
            <!--?php 
            if ( function_exists( 'yoast_breadcrumb' ) ){ yoast_breadcrumb('<p id="breadcrumbs"-->','<p></p>'); } 
            $options = get_nectar_theme_options(); 
            global $options;
            $blog_standard_type = (!empty($options['blog_standard_type'])) ? $options['blog_standard_type'] : 'classic';
            if($blog_standard_type == 'minimal')
                $std_minimal_class = 'standard-minimal';
            else
                $std_minimal_class = '';
                echo '<div id="post-area" class="col '.$std_minimal_class.' span_12 col_last">';
            
            
                 if(have_posts()) : while(have_posts()) : the_post(); 
                    
        
                    if ( floatval(get_bloginfo('version')) < "3.6" ) {
                        //old post formats before they got built into the core
                         get_template_part( 'includes/post-templates-pre-3-6/entry', get_post_format() ); 
                    } else {
                        //WP 3.6+ post formats
                         get_template_part( 'includes/post-templates/entry', get_post_format() ); 
                    } 
    
                 endwhile; endif; 
                
                 wp_link_pages(); 
                    
                    global $options; 
                    if($theme_skin != 'ascend') {
                        if( !empty($options['author_bio']) && $options['author_bio'] == true){ 
                            $grav_size = 80;
                            $fw_class = null; 
                        ?>
                            
                            <div id="author-bio" class="<?php echo $fw_class; ?>">
                                <div class="span_12">
                                    <!--?php if (function_exists('get_avatar')) { echo get_avatar( get_the_author_meta('email'), $grav_size, null, get_the_author() ); }?-->
                                    <div id="author-info">
                                        <h3><!--?php if(!empty($options['theme-skin']) && $options['theme-skin'] == 'ascend') { _e('Author', NECTAR_THEME_NAME); } else { _e('About', NECTAR_THEME_NAME); } ?--> <!--?php the_author(); ?--></h3>
                                        <p><!--?php the_author_meta('description'); ?--></p>
                                    </div>
                                    <!--?php if(!empty($options['theme-skin']) && $options['theme-skin'] == 'ascend'){ echo '<a href="'. get_author_posts_url(get_the_author_meta( 'ID' )).'" data-hover-text-color-override="#fff" data-hover-color-override="false" data-color-override="#000000" class="nectar-button see-through-2 large"--> '. __("More posts by",NECTAR_THEME_NAME) . ' ' .get_the_author().' '; } ?>
                                    <div class="clear"></div>
                                </div>
                            </div>
                            
                    <!--?php } ?-->
                    <div class="comments-section">
                           <!--?php comments_template(); ?-->
                     </div>   
                <!--?php } ?-->
                <!--?php if($blog_header_type == 'default_minimal' && $blog_social_style != 'fixed_bottom_right')  { ?-->
                
                    <div class="bottom-meta">    
                        <!--?php
                            echo '<div class="sharing-default-minimal"-->'; 
                                nectar_blog_social_sharing();
                            echo '</div>'; ?>
                    </div>
                <!--?php } ?-->
            </div><!--/span_9-->
            
            
            
            
        </div><!--/row-->
        
        <!--ascend only author/comment positioning-->
        <div class="row">
            <!--?php if($theme_skin == 'ascend' && $fullscreen_header == true) { ?-->
            <div id="single-below-header" class="<?php echo $fullscreen_class; ?> custom-skip">
                <!--?php if($blog_social_style != 'fixed_bottom_right') { ?-->
                    <span class="meta-share-count"><i class="icon-default-style steadysets-icon-share"></i> <!--?php echo '<a href=""--><span class="share-count-total">0</span> <span class="plural">'. __('Shares',NECTAR_THEME_NAME) . '</span> <span class="singular">'. __('Share',NECTAR_THEME_NAME) .'</span> '; nectar_blog_social_sharing(); ?> </span>
                <!--?php } else { ?-->
                    <span class="meta-love"><span class="n-shortcode"> <!--?php echo nectar_love('return'); ?-->  </span></span>
                <!--?php } ?-->
                <span class="meta-category"><i class="icon-default-style steadysets-icon-book2"></i> <!--?php the_category(', '); ?--></span>
                <span class="meta-comment-count"><i class="icon-default-style steadysets-icon-chat-3"></i> <a class="comments-link" href="<?php comments_link(); ?>"><!--?php comments_number( __('No Comments', NECTAR_THEME_NAME), __('One Comment ', NECTAR_THEME_NAME), __('% Comments', NECTAR_THEME_NAME) ); ?--></a></span>
            </div><!--/single-below-header-->
            <!--?php }
            if($theme_skin == 'ascend') nectar_next_post_display(); ?-->
            <!--?php if( !empty($options['author_bio']) && $options['author_bio'] == true && $theme_skin == 'ascend'){ 
                        $grav_size = 80;
                        $fw_class = 'full-width-section '; 
                        $next_post = get_previous_post();
                        $next_post_button = (!empty($options['blog_next_post_link']) && $options['blog_next_post_link'] == '1') ? 'on' : 'off';
                    ?-->
                        
                        <div id="author-bio" class="<?php echo $fw_class; if(empty($next_post) || $next_post_button == 'off' || $fullscreen_header == false && $next_post_button == 'off') echo 'no-pagination'; ?>">
                            <div class="span_12">
                                <!--?php if (function_exists('get_avatar')) { echo get_avatar( get_the_author_meta('email'), $grav_size,  null, get_the_author() ); }?-->
                                <div id="author-info">
                                    <h3><!--?php if(!empty($options['theme-skin']) && $options['theme-skin'] == 'ascend') {  echo '<i-->' . __('Author', NECTAR_THEME_NAME) . ''; } else { _e('About', NECTAR_THEME_NAME); } ?> <!--?php the_author(); ?--></h3>
                                    <p><!--?php the_author_meta('description'); ?--></p>
                                </div>
                                <!--?php if(!empty($options['theme-skin']) && $options['theme-skin'] == 'ascend'){ echo '<a href="'. get_author_posts_url(get_the_author_meta( 'ID' )).'" data-hover-text-color-override="#fff" data-hover-color-override="false" data-color-override="#000000" class="nectar-button see-through-2 large"-->' . __("More posts by",NECTAR_THEME_NAME) . ' ' . get_the_author().' '; } ?>
                                <div class="clear"></div>
                            </div>
                        </div>
 
             <!--?php } ?-->
              <!--?php if($theme_skin == 'ascend') { ?-->
                  <div class="comments-section" data-author-bio="<?php if(!empty($options['author_bio']) && $options['author_bio'] == true) { echo 'true'; } else { echo 'false'; } ?>">
                       <!--?php comments_template(); ?-->
                 </div>   
             <!--?php } ?-->
        </div>
       <!--?php if($theme_skin != 'ascend') nectar_next_post_display(); ?-->
        
    </div><!--/container-->
<!--/container-wrap-->
<!--?php if($blog_social_style == 'fixed_bottom_right') { ?-->
    <div class="nectar-social-sharing-fixed"> 
        <!--?php
            // portfolio social sharting icons
            if( !empty($options['blog_social']) && $options['blog_social'] == 1) {
                
                echo '<a href="#"--><i class="icon-default-style steadysets-icon-share"></i> <div class="nectar-social">';
                
                
                //facebook
                if(!empty($options['blog-facebook-sharing']) && $options['blog-facebook-sharing'] == 1) { 
                    echo "<a class="facebook-share nectar-sharing" href="#" title="".__(" share="" this',="" nectar_theme_name)."'=""> <i class="fa fa-facebook"></i> </a>";
                }
                //twitter
                if(!empty($options['blog-twitter-sharing']) && $options['blog-twitter-sharing'] == 1) {
                    echo "<a class="twitter-share nectar-sharing" href="#" title="".__(" tweet="" this',="" nectar_theme_name)."'=""> <i class="fa fa-twitter"></i> </a>";
                }
                //google plus
                if(!empty($options['blog-google-plus-sharing']) && $options['blog-google-plus-sharing'] == 1) {
                    echo "<a class="google-plus-share nectar-sharing-alt" href="#" title="".__(" share="" this',="" nectar_theme_name)."'=""> <i class="fa fa-google-plus"></i> </a>";
                }
                
                //linkedIn
                if(!empty($options['blog-linkedin-sharing']) && $options['blog-linkedin-sharing'] == 1) {
                    echo "<a class="linkedin-share nectar-sharing" href="#" title="".__(" share="" this',="" nectar_theme_name)."'=""> <i class="fa fa-linkedin"></i> </a>";
                }
                //pinterest
                if(!empty($options['blog-pinterest-sharing']) && $options['blog-pinterest-sharing'] == 1) {
                    echo "<a class="pinterest-share nectar-sharing" href="#" title="".__(" pin="" this',="" nectar_theme_name)."'=""> <i class="fa fa-pinterest"></i> </a>";
                }
                
                echo '</div>';
            }    
            ?>
        </div><!--nectar social sharing fixed-->
    <!--?php } ?-->
    
<!--?php get_footer(); ?-->

Be.st 

@Mariusz, 

As is mentioned in this ticket you will have to add a single.php file in the Child theme and paste in the code for it to not have a sidebar . 

Thanks

Please open a new ticket with the Admin login Details . 

Thanks