the most obvious issue I see on this page is the form action.
the page you sent me is named registration_prof.php, but the action of the form is set to post to a different page registration.php:
<form action="registration.php"
change that so it is posting to itself:
<form action="registration_prof.php"
if you still have a problem after changing the form action, let me know and i will give a call.