Postfix doesn't work automatically after reboot

hi,

i have problem with Postfix need to be run after every reboot i made

after reboot:

# systemctl status postfix
● postfix.service - Postfix Mail Transport Agent
     Loaded: loaded (/lib/systemd/system/postfix.service; disabled; vendor pres>
     Active: inactive (dead)

then i try:

# systemctl start postfix
# systemctl status postfix
● postfix.service - Postfix Mail Transport Agent
     Loaded: loaded (/lib/systemd/system/postfix.service; disabled; vendor pres>
     Active: active (exited) since Tue 2022-01-25 20:01:52 UTC; 2s ago
    Process: 1688 ExecStart=/bin/true (code=exited, status=0/SUCCESS)
   Main PID: 1688 (code=exited, status=0/SUCCESS)

Jan 25 20:01:52 Starsmt2 systemd[1]: Starting Postfix Mail Transport Agent...
Jan 25 20:01:52 Starsmt2 systemd[1]: Finished Postfix Mail Transport Agent.

I applied this explanation by the way and it may be the cause of the problem:
https://community.cyberpanel.net/t/filtering-spam-in-rainloop-autoreply-and-email-filters-with-sieve/30637

please help

ubuntu 20.04 / VPS by Vultr

Please open a ticket at cloud.cyberpanel.net and I will enable debugger for you