==== REQUIRED BASIC INFO OF YOUR IREDMAIL SERVER ====
- iRedMail version (check /etc/iredmail-release): 2020041601
- Deployed with iRedMail Easy or the downloadable installer? iRedMail Easy
- Linux/BSD distribution name and version: CentOS 7
- Store mail accounts in which backend (LDAP/MySQL/PGSQL):MySQL
- Web server (Apache or Nginx):Nginx
- Manage mail accounts with iRedAdmin-Pro? Yes
- [IMPORTANT] Related original log or error message is required if you're experiencing an issue.
====

Today, one user is affected by being unable to send email.  They can receive email fine.  IP address is not banned in fail2ban and iRedMail is using the fail2ban database add-on.

The user can't send email from any connection - home, mobile and office VPN.  It affects every device.  The can receive email just fine on every device.

Password has not been changed.

For this user only, the following is seen in the logs when they try to send email from an IP where others CAN send email from (smtp -v set for smtp submission in master.cf):

Jun  8 13:09:51 iredmail postfix/submission/smtpd[5942]: > unknown[81.63.185.132]: 221 2.0.0 Bye
Jun  8 13:09:51 iredmail postfix/submission/smtpd[5942]: match_hostname: unknown ~? 127.0.0.1
Jun  8 13:09:51 iredmail postfix/submission/smtpd[5942]: match_hostaddr: 81.63.185.132 ~? 127.0.0.1
Jun  8 13:09:51 iredmail postfix/submission/smtpd[5942]: match_hostname: unknown ~? [::1]
Jun  8 13:09:51 iredmail postfix/submission/smtpd[5942]: match_hostaddr: 81.63.185.132 ~? [::1]
Jun  8 13:09:51 iredmail postfix/submission/smtpd[5942]: match_hostname: unknown ~? 81.63.185.0/24
Jun  8 13:09:51 iredmail postfix/submission/smtpd[5942]: match_hostaddr: 81.63.185.132 ~? 81.63.185.0/24
Jun  8 13:09:51 iredmail postfix/submission/smtpd[5942]: disconnect from unknown[81.63.185.132]
Jun  8 13:09:51 iredmail postfix/submission/smtpd[5942]: master_notify: status 1
Jun  8 13:09:51 iredmail postfix/submission/smtpd[5942]: connection closed

It is only this user affected.

Any ideas?