you are probably using the Oculus Link (cable) right?
I could not pinpoint why/when it does happen but the only remedy is to close the Oculus app on your desktop (to disconnect the Link) and re-enter from Quest home. You do not need to pull the cable and physically disconnect nor quit MSFS. Just re-establish the software link.
For me, it seems that since joining the Public Test Channel under Beta in the app has resulted in no more occurrences of this.
Anyway, good luck.