Your form action is set to post to the thank you page:
<form class="Cool_Default" id="SimpleContact_Cool_Default" name="SimpleContact_Cool_Default" method="post" action="thankyou.php">
leave that blank so universal email has an opertunity to send the email:
<form class="Cool_Default" id="SimpleContact_Cool_Default" name="SimpleContact_Cool_Default" method="post" action="">