Custom Post Type and carousel slider

$args = array(
            'post_type' => 'dzieci',
            'taxonomy' => 'post_format',
            'field' => 'slug',
            'terms' => $terms_query
        );
        
        
        $latestPosts = new WP_Query(apply_filters('kleo_posts_carousel_args',$args));
        
        while ($latestPosts-> have_posts()) :$latestPosts-> the_post();
            
            switch (get_post_format()) {
                
                default:
                        $output .= '<li>';  
                        if (get_post_thumbnail_id())
                        {  
                            $output .= '<div class=""><a href="'.  get_permalink().'">';
                            $output .= '<span class="read"><i class="icon-'.apply_filters('kleo_img_rounded_icon','heart').'"></i></span>';
                            $output .= get_the_post_thumbnail(null,'blog_carousel');
                            $output .= '</a></div>';
                        }
                        $output .= '<h4>'.get_the_title().'</h4>';
                        $output .= '<p>'.  word_trim(get_the_excerpt(), 15, '...').'</p>';
                        $output .= '<p><a href="'.  get_permalink() .'"><i class="icon-angle-right"></i> '.__("ZOBACZ", 'kleo_framework').'</a></p>';
                        $output .= '</li>';
                    break;
            }

        endwhile;
      
        $output .= '</ul></div><!--end carousel-stories-->'.
				'</div>';
		
        return $output;