Welcome,
I am writing, because I have problem in DirectAdmin with distribution lists.
If I send to the list in such a configuration goes with the attachment without a problem, but if I set the moderator, and that meil only this person can send it, I get the back with an error and meil not sended.

If I write moderator meil, it I got email back, --> BOUNCE (mail@domena.pl): Approval required example ->

https://imgur.com/a/7u8GDpz

Could someone help you?
Thanks
Adrian