I got a schemata error while updating phabricator on our production server

Target                                Error  
phabricator_countdown.countdown_timer Surplus

 SCHEMATA ERRORS 

The schemata have serious errors (detailed above) which the adjustment
workflow can not fix.

If you are not developing Phabricator itself, report this issue to the
upstream.

If you are developing Phabricator, these errors usually indicate that your
schema specifications do not agree with the schemata your code actually
builds.

What is weird is that I didn't get this on my local server (I first update phabricator on a local server before moving to production).

Another user had a similar issue (although in another table) as you can see in T6795 and it was safely solved by deleting the affecting tables (after you mentioned those tables did not belong to phabricator and could be safely deleted). In our case it happened in phabricator_countdown.countdown_timer.

Any ideas?