Function change the Post Title and Custom Taxonomy with ACF Front Page Form

acf_check_postname.php

// check if this is to be a new post
    if( $post_id != 'new' )
    {
		if (get_the_title($post_id) != $_POST['acf']['field_5434172d1d00f'] ){
			$update_post = array(
				'ID'           => $post_id,
				'post_title' => $_POST['acf']['field_5434172d1d00f']
			);

			// Update the post into the database
			wp_update_post( $update_post );
			
		}

		$longterms  = vo_bundesland_langeform($_POST['acf']['field_5437aa29f0857']);
		wp_set_object_terms( $post_id, $longterms , 'bundesland');


    }