Hello.
The Villagers like entering in their village well and swim there. However they trying to get out from it but they can't due to well depth. If the villager pathfinding is to explore the whole village then it's likely to enter the village well by mistake and stuck there. They shall be in dangerous from hostile mobs. Please fix it.

Device:
Condor Plume P6 Pro (PGN-518) Smartphone in Android 6.0 Operating System Surface