Compass calibration not sensing the GPS/Compass module in QGC

Hi! I have a cloned Chinese Pixhawk 2.4.8, and recently it entirely stopped responding to attempts to calibrate the GPS/compass. I was able to do this previously in QGC.

Now, when I go to QGC → Sensors → Compass → OK, I get the below screen but no progress in calibration:

Also, I tried to do the claibration via MissionPlanner - same issue, no progress beyond this:

I thought perhaps the GPS/Compass module is bad, so I connected a new unit - same results.

Does anyone have a suggestion what can be done here to complete the calibration process? Or, what to check to trace the issue?

Thanks a lot!