The CVV2 code is the 3 digit code on the back of your card (or the 4 digit code on the front if you are using an American Express).
To troubleshoot please go to the main dashboard of your seetickets.us account.
Then, click on the Account tab on the left navigation panel.
You may see a credit card stored, that you can delete by clicking the little trash can.
Then try making your purchase again. If you are still having trouble please call us for help.