Change confirmation or cancellation email subject

For changing confirmation email you can use following filter hook and paste it into your theme’s functions.php file.

//For changing Confirmation Email Subject
add_filter( 'vczapi_pro_registration_confirm_title', 'vczapi_pro_confirm_title_for_registration', 10, 2 );
function vczapi_pro_confirm_title_for_registration( $content, $meeting_details ) {
$content = 'Registration Confirmation For ' . $meeting_details->topic;
return $content;
}

For changing cancellation email subject you can following filter hook.

//For changing Confirmation Email Subject
add_filter( 'vczapi_pro_registration_canellation_title', 'vczapi_pro_cancellation_title', 10, 2 );
function vczapi_pro_cancellation_title( $content, $meeting_details ) {
$content = 'Registration Cancellation For ' . $meeting_details->topic;
return $content;
}