Not using the payment UPI apps in not working I am so iPhone 6 please update the version may

The last security updates iOS 12.5.7 -> released September 12, 2022, available for iPhone 6.

Sorry, iPhone 6 is an outdated iPhone it can’t be update to a higher iOS (13 and later).

Yes, most apps require iOS 13 or later.

UPI is available for iOS versions 13.4 and higher and iPhone 6s and newer.

Considering a newer type of iPhone?

Read before you buy a newer iPhone: The All Too Common SAD Reality of Buying a Used iPad/iPhone

The All Too Common SAD Reality of Buying … - Apple Community

Apple Store -> iPhone - Buying iPhone - Apple

Apple Certified Refurbished -> Refurbished iPhone Deals - Apple

Additional: see -> About billing for Apple subscriptions and media products in India

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

India

•               Apple ID balance (from adding funds)

•               Net Banking (adding funds only)

•               UPI (adding funds only) -> you cannot use UPI.

You can use / pay with your Apple ID balance, see: 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)

How to redeem your Apple Gift Card or App Store & iTunes gift card

How to redeem your Apple Gift Card or App Store & iTunes gift card – Apple Support (UK)