Why does it say (failed) beside my Mastercard

it jeeps asking for verification

Try this -> to verify your payment method / payment information you need to -> 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.

If you update your payment method or add funds to your Apple ID balance, It would take about 1 to 3 business days in order to process.

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

👍 yes check again after a few days.

Thank you for your feedback and you're welcome.

You may need to check the validity of your Mastercard.