Today, I entered my world and all the mobs I had interacted with,they were not. All the blocks or items remain intact.Please help me,all those mobs mean a lot of progress for me.

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We're tracking this issue in MCPE-144208, so this ticket is being resolved and linked as a duplicate.

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Same - every pet, villager, animal plus all of my minecarts for my autofarms 😞

As well as mine carts, boats, amour stands and paintings are also going