Payments
Never share an OTP, even with someone who sounds official
An OTP means a login or a payment is happening now. Banks, police, and UIDAI do not ask you to read it out.
An OTP is a one-time password sent by SMS or email. It proves that the person holding the phone is approving something right now: a login, a new payee, a card payment, or a SIM change.
Who will never need it
Your bank will not ask you to read an OTP on a call, or to type it into a page they sent.
The police, a courier, and a tax office will not ask for it.
UIDAI does not call you to “update Aadhaar” and then take the OTP. Update Aadhaar only on uidai.gov.in, which you open yourself.
A KYC, SIM replacement, or electricity-bill caller who needs the OTP is trying to finish a change you did not start.
If you already read it out
Hang up. The code is only useful for a short time, so speed matters.
Call your bank from the number on the card. Ask them to block cards or UPI if a payment is in progress.
If the OTP was for email, Google, or Instagram, change that password from the official app and log other devices out.
If the OTP was for a SIM or KYC change, call your mobile operator from another phone and ask them to stop the request.
Then call 1930 if money moved or an account was opened in your name.
If money has already left your account, call 1930 or report at cybercrime.gov.in. This page is awareness information. It does not file a complaint.