How do I remove my debit card number from Microsoft Billing and Account Management?

I'm trying to remove my debit card so Microsoft won't charge me anything else than what I wanted. I removed it from my Xbox Live account but it says it's still on this site still. How do I go about removing my number from there?|||if when you log on and it won't let you delete your card number, then what you should do is make up a 16 digit number and add it to you account, then delete the card number you want off of the account.