Manually update the app
Add a payment method
You might need to have a valid payment method on file, even if the app that you want to download is free.
Resolve a problem with your payment method
Prioritize the download
From the Home Screen, touch and hold the app. From the menu that appears, choose Prioritize Download.
Restart your device
Restart your iPhone or iPad, then check to see if you can download or update apps.