ok, this is quite complicated but when I relog onto a world the amount of xp needed to level up resets to the amount needed for level one, however when I level up, the xp needed to level up reconfigures and works correctly.
This is on my Nokia Lumia 635
Thank you for your report! This issue was, however, reported at an earlier time as MCPE-11070. Feel free to add any information you find relevant in the comment section there.
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