Dear abdullahE,
I have checked your site and it seems that you have some errors in the JS code which prevent the form fields from working properly.
You can see them in the Chrome or Firefox developer's console (press F12 and select Console in the popup window). It will give you the exact locations of errors (the two around lines 1572 and 1764 seem to break the code).
Please let me know if you are satisfied with my answer and if I can help you with any other questions you might have.
Regards,
Paweł