DirectAdmin CustomBuild versions.txt is getting old

I got following email from DirectAdmin server.

New Message: CustomBuild versions.txt is getting old on s1.serverok.in

A new message or response with subject:

CustomBuild versions.txt is getting old on s1.serverok.in

has arrived for you to view.
Follow this link to view it:

http://s1.serverok.in:2222/CMD_TICKET?action=view&number=000000967&type=ticket

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Automated Message Generated by DirectAdmin 1.52.1

Do Not Reply.

DirectAdmin is telling you to update your server.

You need to login to SSH as user root. Then run following commands.