I added the phpinfo.php to the website page and it tells me this:
PHP Version 5.6.40
But that seems to be the php version the Hosting service is using, no?
The technicians there told me they were downgrading their PHP version to their lowest version (5.6) to see whether that took care of my email problem.
Attached is a PDF document showing the results I got when opening the phpinfo.php page