Unable to add payment method

See -> About billing for Apple subscriptions and media products in India

About billing for Apple subscriptions and media products in India - Apple Support

You pay with your Apple ID balance, see 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)

India

• Apple ID balance (from adding funds)
• Net Banking4 (adding funds only)
• UPI4 (adding funds only)

Perhaps those URLs that automatically change to the sender's location

have translated their address online, (to UK) ~ when IN was desired.

• Add money to your Apple ID balance - Apple Support

//support.apple.com/HT208687 (generic URL)

This should now change automatically to each recipient location.

(The exact cause began transition in October 2021.)

Was publicly announced; again stated in 9-to-5Mac.

'Apple no longer accepts credit/debit cards India'

then was again, repeated yesterday online.

These other URLs also change automatically to localization:

• Learn how to check your Apple ID balance.
• You can use your Apple ID balance to buy apps, pay for
• subscriptions, and more. But for some purchases, Apple ID balance can't
• be used. Learn what you can buy with your Apple ID balance.
• Apple ID balance isn’t available in all countries or regions. See if you can pay with Apple ID balance in your country or region.

(And feature was easier to manage, prior to site changes at ASC.)

Good luck & happy trails!🐌🐾🌿

Click on the blue link adding funds ⤵️

India

• Apple ID balance (from adding funds)
• Net Banking4 (adding funds only)
• UPI4 (adding funds only)