Stuck on lunar diplomacy.

I'm at the part where he tans hides then turns them itams. Got 4 hides,400gp,needle ,thread. He just keeps telling me where to get them. So I drop the 4 in inv get 4 more he says he'll do it 400 what a bargain. Then it does it all again saying I need 4 hides I don't currently have the ones in Inv.