I've just set up e-newsletter. I can send a test email

Hello!

I've just set up e-newsletter.

I can send a test email fine, but I can't send a real one.

The e-newsletter dashboard says the newsletter has been sent (to the administrator), but it never showed up.

I have checked my spam folder etc. But the email is nowhere to be found.

Could I have entered the settings wrong in a way where a test email will work, but a real one won't?

Confused.

Thank you!