I don't feel particularly safe when using new sites because it's not just about getting the card. But what if the gift card is made using carded funds? Then you get in big trouble and you can't even explain how you got it when the legal authorities ask.
I've used Bitrefill for a while and can vouch for them. Some users on Telegram sell Amazon gift cards via crypto but again the trust issues about what if the gift card is made using an illegal funding source.
But as RocketSingh said, it's working flawlessly so maybe worth giving it a try and I might buy one as well for 1000 INR

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