3 times i added a domain pointer Domain2.com. it seems to work. but then the other domain i have on it Domain1.com cant send any email anymore.
and when i remove the domainpointer Domain2 it still isnt working.

had to restore a backup to get everything working again. Tried 3 times

also tried to add a domain and then a user same problem.

the error was something like user isnt excising on domain1 while if i try to login to webmail it still works and i can also receive email on that account just not send anymore.