In order to be able to place an order with a gift-card, you would first need to register your card (by calling the card's customer service number). They should either ask for your entire billing address, or simply your zip-code. You might want to ask them how long it takes for their system to update that information, as it may take 24 hours or more. When that information has been updated, you would then be able to place your order (either online or over the phone) as normal.