I am on my survival world and my computer rarely restarts automatically after playing so much and when I open Minecraft windows 10 edition, my world turns into creative and the name of the world also disappears and I have lost everything from my inventory. Please fix.

Steps to reproduce:
1. Create a survival world and play so much in it.
2. Your computer will restart automatically
3. Open minecraft windows 10 edition
4. Your world will turn into creative and you completely lose everything in your inventory