I want to add mg visa on my apple wallet and its not working

See -> Payment methods you can use with your Apple ID

Payment methods you can use with your Apple ID – Apple Support (UK)

fyi: Not all credit & debit cards seem to work with App Store / iTunes Store, try a different one, or preferably a credit card. If your card is not accepted as a paymenf method, you need to contact your bank.

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You cannot add a Debit/Credit Card to Apple Pay if the county that you have chosen under the Apple ID does not support it. (e.g. India)

Adding Credit/Debit Cards to Apple Wallet depends on the country that you live in --> Countries and regions that support Apple Pay