A few days before, i was playing minecraft and i closed it, a few hours later when i opened it again,all my minecraft data(my account,resource and behavior packs, worlds) were just gone. Luckily, i had a backup of all files. Then, today the same thing happened again.
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We're tracking this issue in MCPE-149493, so this ticket is being resolved and linked as a duplicate.
That ticket has already been resolved as invalid. Please take a look at the comments of MCPE-149493 for an explanation why this issue is invalid.
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