Urgently need help! (Assassin's Creed: Liberation)

My mission is to intimidate Spanish soldiers in the swamps by killing them one by one with poison darts, only I don’t have these darts, only I can’t return to orleans with a pistol, and there’s nowhere to buy these darts in the swamps. I don’t know what to do, how it was possible to miss such a bug, it’s a critical bug, you can’t pass the game without it