Hostile mobs not spawning

So I just got the new Minecraft better together update and no hostile mobs will spawn for me. They will generate with the world when i start my world but they won't spawn any other time. And I've tried several nights running around trying to find mobs running through ravines and caverns. Literally the only way I can actually fight a mob is at a spawner like the spider,skeleton,zombie or blaze spawners I found other than that nothing spawns. Not even in the nether I can just casually walk through a fortress on hard with no armor or pots because I'm not getting attacked by anything whatsoever.
And it is not on peaceful, I have tried making a new world and I have tried on all the difficultys the only time anything will spawn is on creative but not on survival. It's really frustrating please help