So I did the slog mission on a early save and I never turned it in until now and after I turn it in to Preston it says mission complete but I get no XP and when I go to my missions it says it's completed and I can't set it as a active quest and when you complete a quest it goes to the bottom portion of the mission list but this mission doesn't and now I can't even talk to Preston all he does is talk about the institute and walks away in the middle of talking I get no interaction menu. Any help?