I've been trying to join a fireteam, since Trials doesn't have matchmaking, for a half hour. I have tried with and without brackets, with and without a space, and none of it works! I'm trying to join using ids of people on steam who have open fireteams and nothing is working. It's really bumming me out, because I'm trying to become more serious about Destiny as a hobby, and thus trying to get more into the activities that don't include matchmaking, like raids, strikes, and trials, and summoner being available made me think this was a sign! But, to be honest, the hardest thing about a nightfall strike for me is finding a fireteam when my friends in my clan can't play. Why is joining a fireteam so difficult on steam?