I had gotten a Amazon Promotional gift card for purchasing an item. The card is worth $20 bucks. So i followed the directions and went to amazon.com/gc to redeem my code. The money was added to my balance and i went to find the item i wanted. So i found what i wanted which was a 1600 point Microsoft card for the Xbox 360, i want it now so i went for the purchase where you get the online code right away. When i selected the option of the online code, The box on the side changed from "add to cart" to "buy and get the code". I selected that option and it brought me to this screen where i have to put in my credit card info. I'm not purchasing this xbox card with a credit card, im purchasing it with the amazon promotional gift card, It gives me options of what card to use, Amazon Visa, Mastercard, visa, american express etc. So my question is how do i purchase this card? i don't know what to put in those boxes or what to do