Pre-paid credit cards like this are notoriously hard to use for online purposes. Mainly because your billing info doesn't match what is attached to the card, so most transactions are declined.
You have to call the company that manages the card(usually the 800 number on the back of the card) and they have to work their magic on their end to make the card usable for online purchases. Generally this involves you giving them your address and name so they can set it as the billing address and name on the card.
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