get second ID from array
Your function is called “replace_thumbnail” so I am assuming you are trying to set/replace the post thumbnail (featured image): function replace_thumbnail($id) { $image_ids = array(); $media = get_attached_media( ‘image’, $id );; foreach($media as $item) { $image_ids[] = $item->ID; } // insert your featured image if (!empty($image_ids[1])) { update_post_meta( $id, ‘_thumbnail_id’, $image_ids[1] ); } // $image_ids_str … Read more