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/not fully functional 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.
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Also, see If your Apple ID is locked or disabled https://support.apple.com/en-us/HT204106 "If you or someone else enters your password, security questions, or other account information incorrectly too many times, your Apple ID automatically locks to protect your security and you can't sign in to any Apple services.
If you use two-factor authentication, you need a trusted device or trusted phone number to reset your Apple ID password and unlock your account. If you have a recovery key, you can also use it to help you regain access to your account. …
If you use security questions with your Apple ID, or if you don't have access to a trusted device or phone number, go to iforgot.apple.com. Then you can unlock your account with your existing password or reset your password. After multiple unsuccessful attempts to unlock your account, your Apple ID will remain locked and you can try again the next day.” Eventually you will be able to enter account recovery. “If you can’t sign in, reset your password, or receive verification codes, you can request account recovery to regain access to your account.” (from Get a verification code and sign in with two-factor authentication https://support.apple.com/en-us/HT204974)
Thus, see Recover your Apple ID when you can’t reset your password https://support.apple.com/en-us/HT204921. Read the whole document carefully.
