Why was my account with the App Store and ITunes disabled

According to the "Related Article," If a message says 'Your account has been disabled in the App Store and iTunes'

Contact Apple Support for help.

If you see a message that says "Your account has been disabled in the App Store and iTunes," contact Apple Support for help.

Click the "Contact Apple support" link in thew document you posted from to find out. Only Apple support can tell you and fix it.