Артефакты "Might & Magic Heroes VI"

Hello! I have a licensed copy of the game. I can't change the dynasty weapon. Anton found the feathers, and he's still carrying them. I want to give him a sword, but I can't. The slots where the feathers are located are inactive, and I can't equip the sword either. What am I doing wrong? Or should I give him the weapon at a specific moment, like at the beginning of the mission when the map is shown? I'm getting desperate. Please help me with some advice.