I am not receiving notification emails

Hi, I have set up the plugin in such a way that the registration of new users only takes place with the approval of the administrator. But when I do the test registration, I did not receive the notification at the admin address. Furthermore, if I enter the profile of the new user (which is awaiting approval), and I approve it, the email of the new user does not even receive the approval notification.
I also installed the WP SMTP plugin, but the problem did not go away.