When you play, sometimes the save icon would appear on the top right and it will stay for the entire gaming session. When you save and quit, the save screen would just stay there and you can only close the game without saving. When you open the world again, all the progress of the previous gaming session is gone
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Thank you for your report!
We're tracking this issue in MCPE-155469, so this ticket is being resolved and linked as a duplicate.
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