My sister and I have been playing in my world in my realm. We teleport to random biomes sometimes to treasure hunt on creative mode and one day she teleported herself to really far coordinates and we reached what looked like the edge of the world. there was like a forcefield-like thing in the game and then the game crashed. And ever since then we cannot get back in. Even attempting to penetrate the realm causes the entire game to crash. When I go to report it to apple or to java this is what the report says: (See Attached)
Please check if that's still an issue for you in 1.13.1.