Phantoms doesn't spawn

Greetings Sir/Mam.

I have seen no phantoms in the last 5 Minecraft Days. My difficult is in normal and i have been AFK Fish Farming for the last 5 minecraft days straight. There was no roof or any type of block or slab over my head.

I think the games mob spawning algorithm is broken or it could be a bug which can be fixed in the future beta or full release.

I'm hoping this problem gets fixed soon
Thank You.