I've been discovering lots of despawned villagers, animals and iron golems within an hour of spawning them or naming them. The problem usually occurs when I clear the app on my phone and reload the world. It spawns me in a different place from where I was standing when I cleared the app and if I was riding a horse or had a dog with me it's no where to be found. The same thing has been happening with villagers I have named and got into a bunker. Sometimes it happens too with Iron ores and emeralds that are in my inventory.
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Thank you for your report!
We're actually already tracking this issue at MCPE-21416, so I will resolve and link this ticket as a duplicate.
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