flyawaygoblin

I don't know if this is happening with other people but when i try to load a world it doesn't do anything and I'm stuck on a flat world if anyone had this problem and fixed it can you tell me how to fix it I don't know if this is happening with other people but when i try to load a world it doesn't do anything and I'm stuck on a flat world if anyone had this problem and fixed it can you tell me how to fix it