I had a large chicken farm which was causing lag (~100 chickens). After I killed the chickens, they reappeared as if nothing happened when I reloaded the chunk (either by closing the game and starting it again or by flying away and returning).
I tried suffocating the chickens with blocks, burning them with lava, but they keep returning and the lag seems to be getting worse after each reload (loading a world takes minutes and major lag).
Villagers are affected, but in a different way: they keep escaping from an enclosure and appear in the exact same spots (after reloading the chunk), even though I led them to their enclosure before.
I'm on Xbox so I cannot share my world here. If anyone needs pictures, videos etc, please let me know!
Related issues
Comments

Thank you for your report!
We're tracking this issue in MCPE-187200, 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.
Quick Links:
📓 Bug Tracker Guidelines – 💬 Community Support – 📧 Mojang Support (Technical Issues) – 📧 Microsoft Support (Account Issues)
📓 Project Summary – ✍️ Feedback and Suggestions – 📖 Game Wiki
-- I am a bot. This action was performed automatically! The ticket was resolved by one of our moderators, and I left this message to give more information to you.