I’m unable to change my credit card number at commerce.microsoft.com

Sometime this year I lost my credit card and had it replaced. About a month ago I started receiving emails from *** Email address is removed for privacy *** saying "We are contacting you because we have been unable to charge your credit card for your Windows Live Hotmail Plus service(s). The following credit card is the current payment method on your billing account:

Credit card type: VISA"

As suggested I logged on to https://commerce.microsoft.com and tried to edit the credit card on file but there's no place to change the credit card number.

I then decided to adde a new payment option (Amex) and associate the card with my current subscription (Windows Live Hotmail Plus). I then tried to remove the Visa card but wasn't able to. When I tried to remove it I got prompted that the card is associated with an MSN account and that I would need to contact support to be able to delete it  - my MSN account was canceled a few years back. 

The support page doesn't give any information as to how to remove the card and there's no phone or email address to send an email to.

Now, I get the same email from *** Email address is removed for privacy *** every week and I'l affraid that my account will be suspended and I end up losing my email.

What do I need to do?