Weird Magic Keyboard problem....HELP!!

My machine is a mac mini (2018)

3.2GHz 6-core Intel Core i7

32GB memory

My magic keyboard will not type an "f".

I have debugged it and reset it (several times), but the problem persists.

I am able to type an "f" with the keyboard viewer (clicking "f" with a mouse) and the key works fine. Here is what else I've done (to no avail):

-Reset Pram/SEC

-Restarted in Recovery mode: disk fix

-Keyboard works fine on different mac.

-I have re-installed the system 10.15.5

Maddening issue...can you help??