Try this if you're experiencing an issue when you update or download apps from the App Store on your iPhone or iPad.
You may need to have a valid payment method on file, even if the app you want to download is free.
If a message says “billing problem with previous purchase” or “verification required”
From the Home screen, touch and hold the app. From the menu that appears, choose Prioritise Download.
Restart your iPhone or iPad, then check if you can download or update apps.