I have a contact form using the Statamic Forms feature. When I submit the form, it correctly saves the submission. I can verify this in the control panel. But it does not send the submission to the email addresses that I configured.

I used mail-tester.com to confirm that emails were not getting lost in a spam folder.

I suspect it is a server/PHP configuration issue. What does the Statamic Forms feature use under the hood to send email? Is there anything I should check regarding the PHP configuration?