Calculator froze (sort of) during normal calculations

[matalog]

I was using my Prime in work today, and it exhibited strange behaviour.

I was doing some simple calculations in the home screen of the Function app, and it was working fine, then I sat it aside for a minute, and went to type in the next calculation. I could type in one number, and then no further numbers would appear when typed. If I pressed the on Key, it removed the first number, and I could type in any single number, and it wouldn't accept any further numbers.

I could press shift then ON and it would turn off, then back on when I pressed ON, but it was still exhibiting the same behaviour after being turned on again.

I connected it to PC to backup everything, and upon disconnection, it said it had to reboot in 3 seconds. When it was turned on after that, it was working as expected from then on.

Has anyone experienced this, or does anyone know what may have caused it, or if it is something that I should be worried about?