==== REQUIRED BASIC INFO OF YOUR IREDMAIL SERVER ====
- iRedMail version (check /etc/iredmail-release): v 1.0
- Deployed with iRedMail Easy or the downloadable installer?  Yes
- Linux/BSD distribution name and version:  CentOS 7
- Store mail accounts in which backend (LDAP/MySQL/PGSQL): MariaDB
- Web server (Apache or Nginx):
- Manage mail accounts with iRedAdmin-Pro? Yes
- [IMPORTANT] Related original log or error message is required if you're experiencing an issue.
====
Hi Huangbin.

Currently, there was an issue and the issue is like this.
There is an ongoing email conversion between another party and us and out of sudden, the email is being tagged as spam and go into our Junk folder. On the logs itself, we did not see any abnormalities except seeing sending and receiving email.

May I check with you why is this happening and is there anyway we can resolve it to prevent legitimate email from being tagged as spam and go into Junk / Spam folder?
Thanks.