If you’re having issues buying anything on XBox 360 and doesn’t even let you login to xbox.com and it keeps kicking you out, there is a chance that one of the credit cards you have stored on record is invalid.
If you read the XBox help on how to remove a payment option, they ask you to go to “Payment & Billing” and this site won’t be accessible either.
Your best bet is to go to commerce.microsoft.com and then to their “payment options” page. Here, you will see your credit card. Click on it and click remove. Add a new payment option if you please. After this, you should be able to access xbox.com and buy things on your xboxCreated: 6th October 2012