Whenever attempting to add a player who has joined a fireteam listing on the iOS companion app to my fireteam in-game while in-orbit, it says "please enter a complete, valid BattleTag". I used to be able to use this function without incident in the past, but now I am both unable to invite other players and they are unable to join me. When I message them via the iOS companion app they note the same error I that receive. I am positive that I am entering the players full BattleTag complete with the correct hashtag designation. I'm looking forward to this issue being resolved.
Cheers.