Suddenly, Pixhawk2 can't recognize the gps's compass

Hello, Guys.

I wrote the post about ‘Can’t Recognize Parameter Value’.
(That Post’s URL : Can't Recognize Parameter Value)
There was an error in my previous post.
I wrote ‘can’t recognize parameter value’, but it turned out that the GPS compass was not recognized.

Because I wanted to solve the problem, I kept the drone under the same conditions.
I have set the parameters of the drone so that they can fly.
And I’ve confirmed that the drones do both manual and automatic flight.
After that, I stored drone for 50 days.
I confirmed it on day 51 by connecting the drone with the mission planner.

Immediately after the power was applied, the status indicator of the FC did not turn on after the yellow LED flashed two or three times.
The connection to the mission planner continued to work well.
And the message ‘PreArm: compass not calibration’ will appear on the initial screen.
I checked the compass that the FC recognizes on the Compass tab. However, I noticed that the FC did not recognize the compass of GPS(Here2).
After several firmware reinstallations, the GPS compass was finally recognized.

I don’t think there is a problem with the firmware, but I would like to know if the same thing has happened.

If you know about this issue, please let me know any information.

I wait for your reply.

Thank you.