Villagers sometimes change trades within professions

Summary: Sometimes our villagers will emit anger particles and change their trades and reset their level back to Level 1 without us breaking their workstations!

Steps to Reproduce:
1. Somehow obtain a villager (/summon villager, spawn egg, etc.)
2. Trade with said villager
3. Wait. It might emit particles (the angry ones) and change their trades, but not professions.

Expected Results:
The villagers never change their trades or levels once traded with.

Observed Results:
The villagers eventually change their trades and reset levels without any player input.

This has happened in one specific world with players on many different platforms, including Windows 10, Android, and iOS.

Edit: This has happened, in addition to that one specific world, on a realm as well.

Edit 2: I may have found the cause of the issue. I think when our villagers don't sleep, they can reset their trades and levels but sometimes they don't. Hopefully that helps!