Holding Shift+On on my HP Prime G2 resets all memory content [EDIT: happens again]

[anyfoo]

Ah, I got it back into that state, and now it reproduces again!

The calculator crashed while I was trying weird CAS stuff in the Polar app (giving the "your calculator had a problem" message), and it rebooted to a clean slate: Custom apps and other memory entry gone, Home settings back to defaults etc.

Since then, every time I press Shift+Up, the HP logo appears, then the screen stays black for a few seconds, then it boots back up with a clean slate again, all memory content I entered in the meantime gone.

Anything else I can do to diagnose this?