Logstash not working when started via systemctl, however it work when manually starting

[baljka]

Hello,

Everything was working fine. However it suddenly stopped working.
Now when I try running command "/usr/share/logstash/bin/logstash --path.settings /etc/logstash" manually, it works fine

When I run command "systemctl start logstash". it doesn't start and doesn't create log (/var/log/logstash/).
I run "systemctl status logstash.service". Following shows:

 [root@localhost ~]# systemctl status logstash -l
     ● logstash.service
        Loaded: loaded (/etc/systemd/system/logstash.service; bad; vendor preset: disabled)
        Active: failed (Result: start-limit) since Thu 2020-12-17 17:40:42 +08; 22min ago
       Process: 19961 ExecStart=/usr/share/logstash/bin/logstash --path.settings /etc/logstash (code=exited, status=127)
      Main PID: 19961 (code=exited, status=127)
 
     localhost.localdomain systemd[1]: Unit logstash.service entered failed state.
     localhost.localdomain systemd[1]: logstash.service failed.
     localhost.localdomain systemd[1]: logstash.service holdoff time over, scheduling restart.
     localhost.localdomain systemd[1]: Stopped logstash.service.
     localhost.localdomain systemd[1]: start request repeated too quickly for logstash.service
     localhost.localdomain systemd[1]: Failed to start logstash.service.
     localhost.localdomain systemd[1]: Unit logstash.service entered failed state.
     localhost.localdomain systemd[1]: logstash.service failed.

What's the problem? Any help is appreciated.

Thanks.