I’m a Sorcerer with Paragon level 166 and I’ve completed all side quests (except for the bugged one) but was never given the pit quest after i hit level 60. I’ve completed a lot of NMD’s but dont know anything about their levels. I’m on Penitent difficultly but cant go up to Torment 1 as i can’t access The Pit and I also can’t access The Undercity. I haven’t been playing very long so I’m a fairly new player. Can anyone please help out a stressed out old lady lol im only 44 but my kids think im old 
Does the pit have a lock symbol on it, in Cerrigar?
I could swear you just have to go to Cerrigar, and by interacting with the obelisk while carrying 3 artificer stones, you can access the pit.