Custom "Title Comment" for spacing page

global $post;

if ('5' == $post->ID || '8' == $post->ID || '15' == $post->ID ){
  add_filter('astra_comment_form_title', 'astra_comment_form_title_string');
  function astra_comment_form_title_string( $default ){
    return __("my custom text", 'astra' );
  }
}