If it's like the most recent codes, you've got to have the card series in your system to redeem it. ie. if the code is valid for anyone who buys a 1060, 1070 or 1080 you have to have a card in your system from that series.
Does it redeem from GeForce experience or from a website?
> I only eat my apples in slices now, beacuase I'm afraid of getting
> sued after taking a bite