==== REQUIRED BASIC INFO OF YOUR IREDMAIL SERVER ====
- iRedMail version (check /etc/iredmail-release): 1.4.0
- Deployed with iRedMail Easy or the downloadable installer?
- Linux/BSD distribution name and version: ubuntu18.04
- Store mail accounts in which backend (LDAP/MySQL/PGSQL): MySQL
- Web server (Apache or Nginx):Nginx
- Manage mail accounts with iRedAdmin-Pro?
- [IMPORTANT] Related original log or error message is required if you're experiencing an issue.
====
Hi guys
i installed iRedMail in my server and its work correctly but now i have a problem:
one server with this IP 65.21.130.240 try to send mail to my server and its receive by my server but rejected with helo command to sender

this message is:

Diagnostic-Code: smtp; 554 5.7.1 <static.240.130.21.65.clients.your-server.de>: Helo command rejected: ACCESS DENIED. Your email was rejected because the sending mail server appears to be on a dynamic IP address that should not be doing direct mail delivery (240.130.21.65)

how to resolve this?