TouchID on MacBook pro not working after repair

I recently had my keyboard and front cover replaced by Apple due to faulty keys getting stuck. Taking the MacBook Pro home after a 2 week wait, I discovered that the Touch ID would not work, and in the Touch ID tab of System Preferences, it showed that I had no finger prints registered. That was odd, as I had registered my fingerprint in the past. Thinking this is due to the new cover, I proceeded to add a new fingerprint but the message said,

Fingerprint limit reached. To add a new fingerprint, remove a fingerprint from any account on this Mac.

I HAD no fingerprints. Apple support then said to try adding a new user and see if my Mac allowed me to add a fingerprint. I did, and still same message.

I was then advised by support to re-install my OS, which happens to be the latest Catalina.

I did that, and still face the same problem.

I have read the online fixes that says to add lines in Terminal. But others have said that this fix is not a guaranteed fix either.

So....

Is there a solution from the Wise Apple Community to this problem? If so, please share as I find myself lost here.

Many thanks