IPod Touch issues! Desperately need help!!!?

When I try to download an app it asks for my Apple ID password, which I give. Then it tells me that I need to put in my account security code, and I do. But every single time I do, it tells me, "Credit card processing is temporarily unavailable. Please try again later." Now, like any normal person, I waited figuring their servers or whatever were busy. But no matter how long I wait, or how many times I try, I keep getting that same error over and over again... Yes the information is correct, yes the card is valid. I really need help on this one!!!!!