==== REQUIRED BASIC INFO OF YOUR IREDMAIL SERVER ====
- iRedMail version (check /etc/iredmail-release): 1.2.1 MARIADB edition.
- Deployed with iRedMail Easy or the downloadable installer? downloadable installer
- Linux/BSD distribution name and version: CentOS Linux release 8.2.2004 (Core)
- Store mail accounts in which backend (LDAP/MySQL/PGSQL): MySQL
- Web server (Apache or Nginx): Nginx
- Manage mail accounts with iRedAdmin-Pro? iRedAdmin-Pro    4.3 (MySQL)
- [IMPORTANT] Related original log or error message is required if you're experiencing an issue.
====
Hello,

our users try to save some options via webmail but receives the error: Service temporarily unavailable

The file /var/log/sogo/sogo.log show the next:
Aug 10 17:09:12 sogod [968]: <0x0x561474cd2180[NGSieveClient]> reconnect ...
Aug 10 17:09:12 sogod [968]: [ERROR] <0x0x561474cd09e0[SOGoSieveManager]> Sieve connection failed on sieve://127.0.0.1:4190/?tls=YES
Aug 10 17:09:12 sogod [968]: 181.49.154.26 "POST /SOGo/so/user@correopremium.com/Preferences/save HTTP/1.0" 503 46/3902 10.064 - - 0 - 32

The file /etc/sogo/sogo.conf have the next info:

    SOGoSieveServer = "sieve://127.0.0.1:4190/?tls=YES";
    SOGoSieveScriptsEnabled = YES;
    SOGoVacationEnabled = YES;
    SOGoForwardEnabled = YES;
    SOGoSieveFolderEncoding = UTF-8;

What is the process to verify this issue and how we can resolve it?

Thanks