Form does not send email

Hello Jason / Ray,

I am trying to create a form using Form Builder: set up the fields, validations, styles and for the form to be emailed.
However, when loading the site live and submitting the form as a test, it does not send it.

I set it up so that it posts to another php page, but instead it reloads the same page prompting that there was a validation error (even thought there is none.)

I trying doing it all over and deleting all dependent files to make sure there weren't any corrupted files and starting all over from scratch. but I still get the same error.

The page the problem occurs is in "request-appointment.php"
The site files are attached