After update world is not syncing and deleted

Our world of over two years recently started saying it cannot save because there's to much data. We try to delete the data and it won't let us. Then we uninstall the game and then our world is gone. Try playing a copy or get it back and it says it's corrupt and failed to sync. So now we've lost our world over two years and it's hardly letting us create a new world as we get the same message sometimes about not enough data or failing to sync. This has never happened before. Really frustrating to just lose a world you've been working on for countless hours for over TWO years, the game is not even working now half the time. We are scared to create a new world because it's saying the same stuff.