Of all the digital payment methods, in general, Credit Card has the maximum level of Fraud Protection. In this instance, it’s undermined by your admission that you handed over the OTP to “him”. But only partially.

Assuming that you did not get any products / services in return for your credit card payment or got something that does not “work as advertised”, you can very well file a dispute with your Credit Card Issuer Bank and claim a refund on the grounds of “Deficiency of Service”.

Banks don’t exactly distinguish themselves with great CX. So they will likely fob you off saying, we can’t do anything because you handed over the OTP to the fraudster. But don’t accept that response. Pushback.

That’s the beauty of credit card payments. It gives you a decent amount of fraud protection even if you’ve done something that Banks warn credit cardholders not to do. Don’t be discouraged by what some sanctimonious jokers say. They may be bankers and academicians but they still don’t know one of the most fundamental principles of credit card: It is not about right / wrong or whose fault it is.

See my answer Ketharaman Swaminathan’s answer to Why did HDFC Bank bill a fraud transaction even when I raised a dispute within 20 mins after the transaction? What can I do now? for modalities.

ByTW, for general information, the above is true only with credit card. Debit Card, UPI / Zelle and other form of Account-to-Account Real Time Payment (A2A RTP) DO NOT enjoy this level of cardholder protection. Had the same incident happened with any of these non credit card payments, you can kiss your money goodbye.

UPDATE-1:

It is important to understand that credit card rules are made by card networks like Visa, MasterCard and American Express. They’re NOT laws of the land.

When an Issuer Bank does not comply with them, you can’t achieve much by escalating to government agencies.

No matter how much the Bank tells you to, never file a police complaint for a credit card fraud case. It’s a shady ruse used by banks sit tight on the case under the pretext that it’s illegal for them to do anything until police notifies next steps.

Above all, be patient and perseverant. Credit card fraud resolutions take months. It’s a war of attrition. Whoever blinks first loses.