I have a problem with the membership registration.

There is no way to register on iPhone 5c (only this particular version) and it displays a message "Please enter a valid e-mail address" regardless what email address you put in.

As a solution I was thinking of changing the validation regex which is probably done in angular but I don't where to find it and how to replace it?

I also welcome other solutions if anybody knows how it can be fixed.

Any suggestions appreciated.

Thanks, PJ