Show category and posts

Hi there!

I try to add a loop through all categories and show the posts within. It’s a cpt with a custom taxonomy “themen”.

I have this code but it doesn’t work:

		    $taxonomy = 'themen';
				$terms = get_terms($taxonomy); // Get all terms of a taxonomy
			
				if ( $terms && !is_wp_error( $terms ) ) {
					
					foreach ( $terms as $term ) {
						$cat_id= $term->term_id;

						?>
							<h2><?php echo $term->name; ?></h2>
						<?php						
						$args = array(
							 	'p' => $pdf,
							 	'post_type' => $post_type,
							 	'post_status' => 'publish', cat=> $cat_id
							);
						
						  $the_query = new WP_Query( apply_filters( 'dkpdf_query_args', $args ) );

						  if ( $the_query->have_posts() ) {
						    					
						  	while ( $the_query->have_posts() ) {
						  	    $the_query->the_post();
						  	    global $post;		
									 ?>
										<div class="dkpdf-content">
					    	    	<?php the_content(); ?>	
										</div>
							
						<?php }
							} else {
					    	echo 'no results';
					    }
					    wp_reset_postdata();
					 }		    
			  }

Any idea, what’s wrong?