By default, Postfix tries to deliver mail directly to the Internet. Depending on your local conditions this may not be possible or desirable. For example, your system may be turned off outside office hours, it may be behind a firewall, or it may be connected via a provider who does not allow direct mail to the Internet. In those cases you need to configure Postfix to deliver mail indirectly via a relay host.
# systemctl list-timers
NEXT LEFT LAST PASSED UNIT ACTIVATES
Tue 2021-01-12 18:09:00 UTC 15min left Tue 2021-01-12 17:39:07 UTC 14min ago phpsessionclean.timer phpsessionclean.service
Это Windows? PG admin шел в комплекте с постгресом?