Please ignore everything that has been said so far, it’s completely irrelevant to your site. It’s a common error that often gets parroted, regardless of how wrong it’s been proven time and time again.
It’s a common mistake that all CORS errors are related to the browser validation system. But that only applies if you’re trying to embed things FROM your site INTO other sites.
If you get a CORS error without any cross site stuff, then the problem is something else. This is not a secret, just documented behavior that everyone seems to ignore. Please see the section " Why do I get a CORS error on the 404 error page" in this article for a bit more information:
In your particular case, it’s not a 404 error, but a 403 error. And looking at the Network tab in my browser, I see that this error is generated by this URL:
http://www.bodyandmind.epizy.com/includes/funcs.php
The reason of this is that the folder includes is not web accessible on our hosting. I don’t know exactly when or why this was done, but the gist is that the includes folder should only be used for PHP scripts that are PHP included into other scripts on your site.
So fixing this is simple: just move that script, and any other script that’s supposed to be accessed by browsers, out of that folder. If you put it in the base folder of your website, or in another folder (like actions), you’ll be able to access it without any problems.