This bug, reported by many people, needs to be reopened.
Villagers are still getting stuck near trapdoors and stairs: they freeze, they are completely unable to move
When you guys are working on it please take some time to make sure it's completely fixed, because sometimes it occurs in a few minecraft days.
We're tracking this issue in MCPE-154106, so this ticket is being resolved and linked as a duplicate.
If you would like to add a vote and any extra information to the main ticket it would be appreciated.
If you haven't already, you might like to make use of the search feature to see if the issue has already been mentioned.
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