Having issues with billing problem

To verify your payment information:

Sign in to your Apple ID account page and edit / update your Apple ID details.

https://appleid.apple.com

On the Sidebar click Payment methods -> then tap Payments Methods and tap Manage payment method.

See again -> Related Article -> If your payment method is declined in the App Store or iTunes Store

👉 Get more help

• If you disputed a charge from the App Store or iTunes Store, contact your financial institution again to authorize that charge and future purchases from the App Store or iTunes Store.
• If you're outside of the United States, you might need to contact your financial institution to allow international purchases.
• In some countries and regions, your payment method might be declined because of changes to local law. Learn about billing and purchases in Europe or what to do if your card is declined in India.
• If you still need help, contact Apple Support.

Check also ⤵️

1.

If you see a message that says "Your account has been disabled in the App Store and iTunes", contact Apple Support for help.

2.

If you can't make purchases or update apps, including free apps, you need to update your payment method or add a new one. 

3.

If your Apple ID is locked or disabled

If your Apple ID is locked or disabled - Apple Support (CA)

-> Get a verification code and sign in with two-factor authentication

Get a verification code and sign in with two-factor authentication - Apple Support

4.

If you can't connect to the App Store, iTunes Store, or other Apple services

If you can't connect to the App Store, iTunes Store, or other Apple services - Apple Support

-> If you tried all of the above steps and you still can’t connect, contact Apple Support.

5.

If you get a message -> Your purchase could not be completed, you need to update your payment method or add a new one. 

If you're still unable to update your payment method, Contact Apple Support.

BTW: you need to optimize the range of the mobile network, see this Apple article:

If you see No Service or Searching on your iPhone or iPad

If you see No Service or Searching on your iPhone or iPad - Apple Support

What happens when you call 1-800-MY-APPLE ?

Is that possible?

If this help, see also: Apple Stores In Nigeria And Their Contacts Address: 

https://gmposts.com/apple-stores-in-nigeria-and-their-contacts-address/

Otherwise I don't know.

Have you try to verify your payment information?:

Sign in to your Apple ID account page and edit / update your Apple ID details.

https://appleid.apple.com

On the Sidebar click Payment methods -> then tap Payments Methods and tap Manage payment method.

I hope they can help you, good luck 🙏

Please let us know.

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