My world isn't loading.

Hi I currently play Minecraft on my Xbox One. I play via disc. My world isn't there that I've spent 300+ hours on. At the bottom of my worlds are 3 games with unknown names which I presume is my main world - however it won't let me open it as it says "Failed to sync world data - Could not sync your world data. Would you like to try again" and never works.

The unknown 3 worlds at the bottom are named:

ngEAAE3aAwA= 

ogUAAI-QDwA=

SpFeY-uoAAA=

All 3 of them worlds say they were last played on 01/01/70