Divi Forms Module not Sending Emails with WP-SMTP

Divi theme just updated to version 3.15

Since this update, no emails have received from the Divi Contact Form Module, when WP-SMTP is installed. Elegant Themes recommended to use an alternative SMTP plugin, and that worked.

Could you look into why WP-SMTP fails to send out emails from the Divi Forms Module?

FYI, our Gravity Forms installs in Divi, continues to work just great with WP-SMTP.

Thanks.