the Universal Email server behavior on the confirm page should be configured to redirect to the success page after the email is sent.
If the universal email server behavior is correctly configured to redirect, there may be a php error occurring, add the following code at line 1 to turn error reporting on:
<?php
error_reporting(E_ALL);
ini_set('display_errors','on');
?>
If you need further assistance, please send a copy of the confirm.php page.