There seems to be no monsters spawning in my world whatsoever above ground. I have my game set to hard mode, but enemies will not spawn. I haven't slept for multiple nights and there are no phantoms. I even travel to areas I have not lit up at all with torches and still have no luck getting monsters to spawn. What's going on? Why are there no enemies in my world? They'll spawn around the monster spawners, the Nether, and the End; just not above-ground in the overworld. This is a major problem because it is a large multiplayer world that my friends and I play on frequently. 

I play on the latest version of Minecraft on my Xbox One S, the difficulty is set to hard, it is a purely survival world (no cheats have been used at all), and the world size is about 500mb. Can anybody tell me what the problem is?