Replace faulty item only not the box

I bought a magneto powerstation (Order #***) for 3200 and the item is faulty after two weeks. Unfortunately I dont have the box but I have sufficient proof to show when i bought it and how much. I am request that the item be fixed or replaced. they can keep the money I still need the production but functioning, I dont need the working unit to come in a box they can use it for the faulty item.