==== REQUIRED BASIC INFO OF YOUR IREDMAIL SERVER ====
- iRedMail version (check /etc/iredmail-release): 1.6.0
- Deployed with iRedMail Easy or the downloadable installer? no
- Linux/BSD distribution name and version: ubuntu20.04
- Store mail accounts in which backend (LDAP/MySQL/PGSQL): MySQL
- Web server (Apache or Nginx):Nginx
- Manage mail accounts with iRedAdmin-Pro?no
- [IMPORTANT] Related original log or error message is required if you're experiencing an issue.
=====

There was no problem using the server a few days ago~ Later, I used the FOXMAIL client~ A total of 150 users were added~ It was batched~ I found that it could not be added today~ Later, the query may be that the same IP cannot exceed 30 users, and later changed /etc/ dovecot/dovecot.conf file ~ changed 30 to 10000, but still can't use FOXMAIL to connect~

Please help! Thanks!