TAC/OTP

A Transaction Authorisation Code or One-Time Password — a short-lived numeric code your bank sends to confirm you (and only you) are authorising a transaction. No bank or government agency will ever legitimately ask you to share, forward, confirm, or read one out. A message that simply notifies you of a code ("Your OTP is 123456, do not share this with anyone") is normal; a message that asks you to hand it over is the scam.