Itunes, unable to edit/add/update any billing info, account on file is expired

I am not able to do any app updates because my payment is coming back declined. The credit card that is in my account must be an old debit card number that just expired. It won't let me add a new payment and it won't let me delete the out dated payment. It keeps asking me for the security code but I don't have the card so I don't know it. I don't know why it won't let me add a new payment but it just keeps bumping me back to fix the old payment. It won't even let me change anything other than the security code. Otherwise I'd just put the new debit card info in. HELP! So frustrating. I've tried this on my phone and computer with no luck.