Unable to start Mattermost service in Ubuntu 15.10: getting error as "Failed to start mattermost.service: Unit mattermost.service failed to load: No such file or directory"

description "Mattermost Service"

start on filesystem or runlevel [2345]
stop on runlevel [!2345]
setuid cbadmin
setgid cbadmin
respawn
chdir cbdadmin/mattermost
exec bin/platform
cbadmin@localhost:~$ sudo service mattermost start
Failed to start mattermost.service: Unit mattermost.service failed to load: No such file or directory.

Please help me to resolve this issue.