I ordered a gpu from a seller that said it had cosmetic wear but was fully functioning....the graphics card did not work. So I asked for a refund, started the process and got ghosted. Then on the last day for the refund, the seller opened a case and said that I didn't send back the right item, I know I sent the right item back and have pictures to prove it. However, I'm kind of new to eBay and don't know what to do now...help plz?