iPhone SE gyroscope intermittent, works after reboot

The gyroscope on my iPhone SE only works intermittently now, meaning the phone can't always be tilted upwards to show the home screen, change orientation of apps by rotating the phone, or use any apps (compass, games) which require tilting to operate.

The strange thing is, when it stops working, a warm reboot will solve the issue for some length of time. This leads me to believe it can't solely be a hardware issue (although it's quite old and has been a little battered over time, so it wouldn't be a surprise).

Then again, it surely can't be purely a software issue. It's odd. Has anyone come across this? I've not done anything like locking screen orientation (though this wouldn't stop other things working). It's very strange.