I have just recently downloaded the Caves and Cliffs update for my x box one. Not the xbox one edition. However after this update I had experienced extreme unresponsiveness from my system. After hard reseting my console I saw my 240 my world in which I spent a lot of time had been deleted without my consent.
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We're tracking this issue in MCPE-109144, so this ticket is being resolved and linked as a duplicate.
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