Pixhawk 4 GPS module Compass Calibration problem

I have been using the holybro pixhawk 4 and GPS module for a few months now on the ground and have calibrated the accelerometer and compass multiple times. I am about to lace it into the plane and did one last compass calibration but it will not calibrate anymore. The GPS module compass will fill up the green bar before making the unhappy noise and going back to the empty bar.
I’ve tried the steps in the arduplane wiki including:
Going outside away from metal and computers
Changing the fitness to relaxed
Raising the compass_offs_max to 3000

Is there anything I’m missing? Is it necessary to enable the GPS compass when the pixhawk one calibrated fine? Its going in a fixed wing plane.

I’ve just tried it with a different GPS module and it still won’t pass calibration.