Getting error 503 after unexpected shut down

here are the config files of zamad web services, i see no issue there

[Unit]
StopWhenUnneeded=true
Requires=zammad-web.service
After=zammad-web.service

[Service]
Environment=APP_PROCESS_INDEX=1
ExecStart=/usr/bin/zammad run web
Restart=always
StandardOutput=syslog
StandardError=syslog
SyslogIdentifier=%n

[Install]
WantedBy=zammad-web.service
helpdeskadmin@helpdeskadmin:/etc/systemd/system$ cat zammad-web.service
[Unit]
StopWhenUnneeded=true
Requires=zammad.service
After=zammad.service

[Service]
# this service is just a placeholder
ExecStart=/bin/sleep infinity

[Install]
WantedBy=zammad.service
helpdeskadmin@helpdeskadmin:/etc/systemd/system$}`````