Why can't I download anything on my iPhone?
Why can I download anything on my phone
[Re-Titled by Moderator]
iPhone SE, iOS 14
If you can't make purchases or update apps, including free apps, you need to update your payment method or add a new one.
See also the following Apple articles:
Add money to your Apple ID balance
Add money to your Apple ID balance - Apple Support (IN)
What you can buy with your Apple Gift Card or Apple ID balance
What you can buy with your Apple Gift Card or Apple ID balance – Apple Support (UK)
Payment methods you can use with your Apple ID
Payment methods you can use with your Apple ID – Apple Support (UK)