==== Provide required information ====
- iRedMail version and backend (LDAP/MySQL/PGSQL):
- Linux/BSD distribution name and version:
- Any related log? Log is helpful for troubleshooting.
====

We have been getting lots of spam using the following Technic.

Mail from usually from the sames user but the domain changes all the time, they are using dkim etc to bypass filters etc. Is there a way to block as follow

username@*

We tried in the blacklist in iredmailadmin but no luck any other advice?

Thanks