A world I was playing on yesterday night, has become unplayable. The world appears to be grayed out, and when I attempt to start the world, or edit its properties. I get the message that states "syncing user data." It looks as if it's loading, and then the game just crashes.
Thank you for your report!
However, this issue has been closed as a Duplicate of MCPE-35364.
Please add a vote and any new information to the main ticket, which will be updated accordingly.
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