How to fix error starting mailman on cPanel server

The mailman error I got looks as below:

root@server1 [/usr/local/cpanel/3rdparty]# /usr/local/cpanel/scripts/restartsrv –wait –force mailman
Waiting for “mailman” to start ……info [restartsrv_mailman] systemd failed to start the service “mailman” (The “/usr/bin/systemctl restart mailman.service –no-ask-password” command (process 444759) reported error number 1 when it ended.):

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