when I try to add a credit card it says "iTunes account disabled"

If you see a message that says 'Your account has been disabled in the App Store and iTunes'

If you see a message that says "Your account has been disabled in the App Store and iTunes," there might be a problem with the payment method that you have on file.

When you see the message, don't try to edit any of your account information. Instead, contact Apple Support for help.

The Apple recommended support link below has not been consistently available recently. It is down now. (5:59 am) So if it is not working when you need it, then use one on the other support links I posted below to contact Apple support.

See If you see a message 'Your account has been disabled in the App Store and iTunes' https://support.apple.com/en-us/HT208856. This link says: "There might be a problem with the payment method that you have on file. When you see the message, don't try to edit any of your account information. Instead, contact Apple Support for help.”

Try using the Apple recommended support link above first. But, this site is down very often. Use the support options I give below if necessary.

You can use Apple Support Twitter https://twitter.com/AppleSupport  There may be a wait of an hour or so.

And, if necessary, go here to contact iTunes worldwide support via text or chat https://support.apple.com/choose-country-region/itunes After choosing your country, see the heading, Tell us how we can help.