Mattermost service can't start

I use MySQL 8.0.4 database. mattermost.service`content show as below:
[Unit]
Description=Mattermost
After=syslog.target network.target mysqld.service

[Service]
Type=notify
WorkingDirectory=/opt/mattermost
User=mattermost
ExecStart=/opt/mattermost/bin/mattermost
PIDFile=/var/spool/mattermost/pid/master.pid
TimeoutStartSec=3600
LimitNOFILE=49152

[Install]
WantedBy=multi-user.target

run a ls -lAh command display result as follow:
[root@localhost ~]# ls -lAh /etc/systemd/system/mattermost.service
-rw-rw-r–. 1 root root 315 Sep 11 10:31 /etc/systemd/system/mattermost.service

the output of journalctl -xe as follow:
[root@localhost ~]# journalctl -xe
Sep 14 11:25:49 localhost.localdomain org.gnome.Terminal.desktop[545259]: # wat>
Sep 14 11:25:49 localhost.localdomain org.gnome.Terminal.desktop[545259]: # wat>
Sep 14 11:25:49 localhost.localdomain org.gnome.Terminal.desktop[545259]: # wat>
Sep 14 11:25:49 localhost.localdomain org.gnome.Terminal.desktop[545259]: # wat>
Sep 14 11:25:49 localhost.localdomain org.gnome.Terminal.desktop[545259]: # wat>
Sep 14 11:25:49 localhost.localdomain org.gnome.Terminal.desktop[545259]: # wat>
Sep 14 11:25:49 localhost.localdomain org.gnome.Terminal.desktop[545259]: # wat>
Sep 14 11:25:49 localhost.localdomain org.gnome.Terminal.desktop[545259]: # unw>
Sep 14 11:25:49 localhost.localdomain org.gnome.Terminal.desktop[545259]: # wat>
Sep 14 11:28:27 localhost.localdomain systemd[1]: Starting Check PMIE instances>
– Subject: Unit pmie_check.service has begun start-up
– Defined-By: systemd
– Support: https://access.redhat.com/support

– Unit pmie_check.service has begun starting up.
Sep 14 11:28:27 localhost.localdomain systemd[1]: Started Check PMIE instances >
– Subject: Unit pmie_check.service has finished start-up
– Defined-By: systemd
– Support: https://access.redhat.com/support

– Unit pmie_check.service has finished starting up.

– The start-up result is done.