This is probably because your cards isn't enabled for 3D secure which our bank requires. 3D secure is a standard set up by Visa and MasterCard and is also called Verified by Visa and MasterCard Secure Code.
It may also be that your bank or credit card company is blocking the transaction for some reason. Please make sure that your card is enabled for purchases abroad and specifically from Sweden (Europe).
Please also double check that you have entered expire date (month and year) in the correct order.
Please try to pay with your card using PayPal instead. They normally accept more cards.
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