Please help me my app store has been disabled am not allowed to download any app

See this link and contact apple support when they are open, this is not an issue that you can solve by yourself

If your Apple ID is locked or disabled - Apple Support

See the Apple Support article(s) below. 

If you see a message that says 'Your account has been disabled in the App Store and iTunes' - Apple Support.   *

Contact iTunes Support for assistance. See the Apple Support articles below for contact information.   

iTunes Support – world wide   -

Apple Support schedule phone call     -

Billings and Subscriptions   -

Apple on Twitter