Part of the world got deleted

So my world just started to get giant holes (up to 50 blocks wide) And everything from hight bedrock to 256 blcks in the sky got deleted . Me and my friend worked so hard on that world, we were crying when just parts were disepering with all our pets, items and house.

I hope this dosen´t happen to anyone else bc it is horrible.

I hope you can get right to this Mojang 

Love: Janina   (im sorry for my english, im a finn and I dont know how to take a screeny on bedrock)