[Not Being Able To Get Ayatan Sculpture Duplicates]

I've been running a lot of ayatan sculpture runs lately, and i've seen that i can't get duplicates, if i already have the sculpture (any scuplture) and i do a mission, get the sculpture and extract, it doesn't show up in the mission rewards screen, or my inventory. I have to sell the ones i own, and then do missions. I can get different sculptures, but not the same sculpture multiple times (sculpture duplicate)