Charging for something I don't have

After scrutinizing my statements, I have noticed I am being charged double for my Garage Card. I contacted Platinum Card, they notified my that I have TWO garage cards (sic). I only have ONE garage card in my possession and always have. I requested that this be clarified and that I am refunded, however, they maintain the position that I MUST pay for both. I have never requested a second card, NOR have I ever received a second card. Why MUST I pay for it?? They just don't care. I must pay. No sorry, or we will look into it. JUST PAY.