MYBB registration is not working as it should

I need some help. I have set up my new MyBB to require an email notification, but when I tested it, it allowed a new account to be created and never sent an email notificiation.

This is the setting in the Control Panel of the Admin:

I’m not familliar with where in admin settings of myBB it’s located but check that the email address the mail is FROM is a valid email address Mail generated from the web server MUST be FROM your domain.