This is a bug that stops you from entering your world. What happens is when you don't have very good cell Service and you open a world while signed into a Microsoft account and while In that world you sleep in the bed and the game crashes while you are in the bed and somehow ends up auto saving with you in the bed. When you try to open the world again, the leave bed message is displayed and the game goes back to the title screen for a few frames before crashing.