What to do after [or before] you change your Apple ID [email address] or password - https://support.apple.com/HT204071 - "After you change your Apple ID email address or password, you might need to update your sign-in information with any Apple services you're using." - Or if you're seeing persistent disabled messages or repeated requests for the password to your previous Apple ID.
If you cannot resolve it yourself:
Contact Apple for help with Apple ID account security - https://support.apple.com/HT204169