Me too, same issue reported here with several upvotes already:
https://bugs.mojang.com/browse/MCPE-39810
Derek you might want to upvote the issue in this post: https://bugs.mojang.com/browse/MCPE-39810
Several people have already voted on the issue and we'll have better luck in numbers. 😉
I'm having this issue too, it happened twice and I've lost almost 60 levels of XP 😞
I play on a PS4 and it seems like this issue has to be resolved every other slight update. I've updated my game earlier today and I've tried to get into the game many times, but it always gets stuck on the white Minecraft screen that comes after the Mojang one.