The real scenario

Meena, a schoolteacher in Nagpur, noticed her phone had no signal around 2 PM on a Tuesday. She assumed it was a tower issue and set the phone aside. By evening, when she borrowed a colleague's phone to call her network helpline, she discovered her SIM had been "ported" to a new card earlier that day. In those four hours, the scammer — armed with her Aadhaar number and bank account details purchased from a data breach — had logged into her bank app using OTPs, added a new payee, and transferred ₹1.8 lakh in multiple transactions under ₹50,000 each to avoid triggering alerts.

How do they get your SIM deactivated?

A SIM swap happens when a fraudster visits a telecom retailer or calls the operator's porting helpline and convinces them to issue a new SIM card for your number. Under TRAI regulations, a mobile number can be ported with just a few pieces of identity verification. Scammers obtain the required details — your full name, Aadhaar number, date of birth, and sometimes the last four digits of your existing SIM — from data leaks, phishing calls, or purchased datasets available on dark web forums.

Some scammers go further: they call you pretending to be from your telecom operator, claim your KYC needs updating, and during the conversation extract the information they need. A few operators have been reported to have corrupt retailer staff who process fraudulent port requests for a cut of the proceeds.

Once the new SIM is active, your original SIM goes dead. The scammer now receives every SMS OTP, UPI transaction alert, and bank notification sent to your number. With that access, they reset UPI PINs, add new beneficiaries, and drain accounts within hours — all while your phone sits uselessly showing "No Service."

🚩 Red flags to watch for

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Your phone loses network signal completely for more than 30 minutes, especially during daytime hours when your area normally has good coverage.
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You receive a call or SMS from your telecom operator about SIM porting or KYC update that you did not initiate.
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You get OTP SMS messages for transactions you did not initiate — this means the swap is already in progress.
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Someone calls you claiming to be from your bank or operator and asks you to confirm your Aadhaar number, SIM serial number, or last-call details.

✅ How to stay safe

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Call your operator immediately: If your phone loses network for more than 30 minutes, call 198 (Airtel), 198 (Vi), or 1800-110-009 (BSNL) from another phone. Ask if a porting request has been made.
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Set a SIM lock PIN: Most Android phones and iPhones allow you to set a PIN on the SIM card itself. Even if the physical SIM is stolen, it cannot be used without the PIN.
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Use app-based 2FA where possible: For banking apps, prefer OTP via the bank's own authenticator over SMS. App-based OTPs are tied to your device, not your phone number.
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Set a UPI transaction limit: In your bank's UPI settings, reduce the per-transaction and daily limit to an amount that matches your typical usage. This limits damage even if access is compromised.
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