When i get to this part of the game and try to save it does this... i found it only happens when you get the "searching for artifacts" quest

Having trouble reproducing it. The error message seems like it's having trouble saving an item in an NPC's inventory. I'll take a closer look. Did you post this on the Discord? I think I saw a similar bug there, if not the same. EDIT: It was in another bug post. My bad.