Can't renew my Norton protection. why?

So, recently Norton warned me that my protection was running out, and the automatic renewal didn't work, because I have switched card information since last time.

 

So I go to the page to update my billing information, and fill in my updated credit card information. But it keeps telling me that the number is wrong, and won't accept it. I've done it several times now, and I am not putting in the wrong numbers. And yes, the card is up to date, active, filled with LOADS of cash that I just want to throw at internet security, but god damn it...

 

So if I update my billing information, it looks like it have accepted it, but on the main page, it still says I have to update my billing information. So if I try to save the information (the correct information that was already saved the last time I put it in) without making any changes to it, it says the card number is invalid.

If I try to write in my number again, it accepts it after I save it, but again, if I try to save the page without making any changes, it says it's invalid. So now I can't get it to accept my card, and I've got 13 days left. What do I do?