This is from the Majang website
We're sorry to hear that you're having difficulties with your purchase. Because payment errors could be caused by any number of steps in the payment process, they're often difficult to track down. If you can't purchase the game, first try your purchase on another web browser or device. Please see below for a list of possible purchasing issues.
Purchases through Mojang may be international purchases for those outside of Europe. If a credit or debit card payment is not going through, you may want to contact your card company to ask about the status of the transaction.
Paypal is not currently an option for purchasing a Minecraft gift code online. However, you can still purchase a Minecraft account using Paypal.
Due to US law, many or all prepaid debit cards (such as Visa Vanilla) purchased in the US will not work for Minecraft purchases, as the company is located outside of the US.
Gift codes cannot be purchased in the US at this time. You may want to look into a prepaid card
, which is available in many parts of the world.