i have a custom post type where a post is generated by a form submit. One key is an array which should be stored in a custom field… i shortended the code below to the important part -> they key is “event_musikstil”

'meta_input' => array(                          
             // Custom Fields
                'event_musikstil' => foreach( $event_musikstil as $item ) { add_post_meta( $post_id, "_event_musikstil", $item ); },
                )