Not able to download apps

I guess that's a newly created Apple ID, if that's the case, you need to Add a payment method to your Apple ID - Apple Support

Don't worry it won't charge you anything. after the verification is done you can remove your payment method. Remove a payment method from your Apple ID - Apple Support

If it's an old Apple ID, maybe you have an outstanding balance, you can view if you have any unsettled balance from below link

Check your Apple Account balance - Apple Support

Or sign in to reportaproblem.apple.com. to check for any purchases you've done with your Apple ID, sometimes you've downloaded a trial version of an app and it charges you after the trial period ends and you have an unsettled balance.

Hopefully this answers your question.

Try to sign out from App Store and restart your iPhone and resign in on AppStore and see if the issue is fixed.

Hey there,

Make sure that you entered the right password for the Apple ID that used to to download that app !

if you see error message, please provide a screenshot for it .

In this case you have to Contact Apple for support and service - Apple Support