SIM Swap and Duplicate SIM Fraud over the phone

How it looks over the phone, the red flags and what to do.

A phone call lets the scammer talk fast, sound confident and keep you from thinking. The caller ID can be faked, so it proves nothing. SIM Swap and Duplicate SIM Fraud is one of the ways this shows up: Fraudsters get a duplicate SIM for your number, take your OTPs and empty accounts. Sudden loss of signal can be the first sign. Learn the steps.

What sim swap and duplicate sim fraud looks like over the phone

• An unknown or international number, or a number that looks like a real office.
• A calm, official voice that already knows your name or the last digits of your card.
• Being told to stay on the line and not to tell your family.

The scammer first collects enough about you to pass a SIM replacement request: your name, date of birth, address and Aadhaar details, bought, leaked or tricked out of you. They also learn which bank you use. Sometimes a caller poses as the operator and asks you to press a key or share a code to 'approve an upgrade', which actually approves the replacement.

Red flags to check on the phone call

• Your phone loses network for hours while others work.
• A caller asks you to reply with a code to approve an upgrade.
• You get an unexpected message about a SIM replacement.
• Bank alerts stop arriving or arrive on other channels only.
• You are told that a case, arrest, block or penalty is coming within minutes.
• You are asked to move money to a "safe account".

What to do

1. If you lose network suddenly, use wifi to contact the operator through its official app or the number on your bill.
2. Ask your bank, through its official app on another device, to lock net banking and UPI.
3. Never approve a SIM change by replying to a message from a caller.
4. Call the bank or office on the number printed on your card, bill or official app, not on a number the caller gave.
5. Never share an OTP or PIN. No genuine staff member needs it.
6. If you already installed an app on the call, uninstall it and switch on airplane mode, then call your bank at once.

Report the number on the Sanchar Saathi portal (Chakshu facility). If money moved, call 1930 immediately.

If money or a code is already gone

1. Call 1930 right away and tell them the loss and the times.
2. Contact your bank through the number on your card to block accounts and cards.
3. Ask the operator to block the duplicate SIM and restore yours.
4. File a complaint on cybercrime.gov.in and change email and banking passwords.

National Cyber Crime Helpline: 1930; report at cybercrime.gov.in.

Safeavio Sentinel's anti-theft feature includes a SIM-change alert, so if the SIM in your phone changes you can be told. The scam check reads a pasted message or call note and flags requests to approve an upgrade or share a code. It cannot detect a swap done on the network side, and it does not replace calling your operator and bank, which is what restores your number.

Full guide: SIM Swap and Duplicate SIM Fraud: how it works, signs and what to do. Other channels: SMS, fake app.

Questions