The main reason is that you have not done the online verification for your credit card. That is free service provided by the credit card company to guarantee the secure online shopping for customers. Please contact your credit card issuer bank for more information.

Please click on following links to learn more about 'Verified by VISA' and 'MasterCard SecureCode'.

https://usa.visa.com
http://www.mastercard.com

If you don't want to register 'Verified by VISA' or 'MasterCard SecureCode', you can make your payment by PayPal.