Compass calibration; need some help please

I am looking at this page in MissionPlanner…

I have only one compass, which is in the Pixhawk4.

Why does it have a box ticked for compass 2?
Why does ‘remove missing’ not remove the tick on compass 2?

In the screen as seen, I have hit ‘start’ and moved the flight controller .
None of the bars shows progress.

Would it suffice to remove the flight controller from the bench and all connected to it, stick it into a mobile 5V battery via USB, without connecting anything to it, other than the telemetry radio, go outside and move the controller in all directions as seemingly required?

You’ll be using GPS for yaw. Ignore the compass. Uncheck the “use” tick mark.

Thanks; I have done all the first set-up tasks, except this one.
Unticked both now and rebooted.