==== REQUIRED BASIC INFO OF YOUR IREDMAIL SERVER ====
- iRedMail version (check /etc/iredmail-release):  0.9.6 OPENLDAP edition
- Deployed with iRedMail Easy or the downloadable installer?
- Linux/BSD distribution name and version: centos
- Store mail accounts in which backend (LDAP/MySQL/PGSQL):  ldap
- Web server (Apache or Nginx): apache
- Manage mail accounts with iRedAdmin-Pro?
- [IMPORTANT] Related original log or error message is required if you're experiencing an issue.
====
Hi, how to stop this:

fake acconuts @mydomain.org send to the same accounts @mydomain.org emails:
they are blocked but generate traffic...

Feb 21 19:15:34 mail postfix/postscreen[5120]: DISCONNECT [45.8.44.57]:45478
Feb 21 19:15:34 mail postfix/smtpd[6053]: NOQUEUE: reject: RCPT from unknown[197.15.110.56]: 550 5.1.0 <matsulov@mydomain.org>: Sender address rejected: User unknown in virtual mailbox table; from=<matsulov@mydomain.org> to=<matsulov@mydomain.org> proto=ESMTP helo=<[197.15.110.56]>

or

Feb 21 19:20:52 mail postfix/postscreen[5120]: DNSBL rank 2 for [187.160.10.98]:28282
Feb 21 19:20:54 mail postfix/postscreen[5120]: NOQUEUE: reject: RCPT from [187.160.10.98]:28282: 550 5.7.1 Service unavailable; client [187.160.10.98] blocked using b.barracudacentral.org; from=<miroslawa@mydomain.org>, to=<miroslawa@mydomain.org>, proto=ESMTP, helo=<CableLink-187-160-10-98.PCs.InterCable.net>

I have iredmail packet installed (fail2ban, amavis,clamd etc ).
tnx