Thanks all for your comments...
What I mean is, that with that codes everything is working fine on the same script.....
that script is name : admissions.php and if everything works fine then it calls itself.
That's working perfect, but in my side.... I mean, working fine using my PC, but when I uploaded to my hosting, then the only thing that fails is that part : header("Location: admissions.php?success");
that part is not reloading the page again, or in other words, no calling again the script admissions.php with ?success
.