About Gss And Yarn?

i would like too report this problem :O
the problem is ive been hunting gs so i got 100 gss and when i was going too change them too spoon of spider silk (yarn)
the npc wasnt there and i ask in trade/help if it was an other way and every1 is saying a GM need too do it for me or it may work if i "skin" them with my obsidian knife? but i rly want too change them so i can get summoner addon so fix it or a GM please msg me in-game ( my name is Warrior Khan Phan )

i will fix npc in next update.