I have no link for mobile carrier. I have T-Mobile.

Hi

Mobile phone billing requires carrier support. This payment method option is currently available with certain carriers in selected countries (presently Germany, Japan, Russia, Switzerland and Taiwan).

If your carrier does not yet offer this option, you may wish to let them know.

Feedback can also be sent to Apple here:

https://www.apple.com/feedback/iphone.html

To set up the payment method if it is supported by your carrier:

Set up mobile phone billing as your payment method in the iTunes Store, App Store, or iBooks Store - Apple Support

Jrmcdade wrote:

I live in the United States. Is T-mobile not supported in the US?

As the article advises, "Mobile phone billing is currently available with select carriers in Germany, Japan, Russia, Switzerland, and Taiwan".