SIM swap fraud: my cellphone suddenly has no signal, what do I do?

SIM swap fraud: my cellphone suddenly has no signal, what do I do?

You are at home, at work or out, somewhere you always have signal, and suddenly your phone shows "No service" or "Emergency calls only". You restart it and nothing changes. The person next to you on the same network has signal. It could be a network problem or load shedding knocking out a tower, but it could also be SIM swap fraud: someone has convinced your network to move your number to a new SIM card (or an eSIM), and from that moment they receive your calls and, above all, your SMSs with banking OTPs. In this situation minutes matter, and there is a specific order in which to act.

How does a SIM swap work?

The fraud almost never starts on the day you lose signal. It usually has three stages:

1. They collect your details. Through a fake SMS or email from your bank, a call pretending to be from your network or your bank, or data from earlier breaches, they get your name, ID number, cellphone number and, often, your online banking login.
2. They impersonate you to your network. With that data, sometimes with a forged ID or affidavit, they ask for a replacement SIM or an eSIM, claiming the phone was lost or stolen, at a store, by phone or through an online account.
3. They use your number to get into your accounts. When the new SIM is activated, yours stops working. Now they receive the OTPs by SMS and can approve payments, add beneficiaries, link your card to a phone wallet, reset your email passwords or take over your WhatsApp.

That is why they often strike after hours, on weekends or on public holidays: they are counting on you taking hours to notice.

What are the warning signs?

• You suddenly lose signal somewhere you always have it, and restarting does not fix it.
• Shortly before, you got an SMS or email from your network about a SIM swap, an eSIM activation or a change of details you did not ask for.
• You receive alerts from your bank or email about new logins, password changes, new beneficiaries or a new device.
• WhatsApp logs you out with a message saying your number has been registered on another phone.
• A few days earlier you got an SMS or a call "from your bank" asking for details or passwords, and you gave them.

One sign on its own proves nothing. Losing signal plus any alert about changes to your accounts is reason enough to act now.

What do I do right now?

Follow this order. You will need another phone (a family member's, a colleague's or a landline) or internet access over Wi-Fi.

1. Call your network from another phone. Use the official customer care number from its website or your bill, never one sent to you by SMS. Ask whether a SIM swap or eSIM has been processed on your number. If so, ask them to block the new SIM immediately and record that the request was fraudulent.
2. Call your bank's fraud line. The number on the back of your card or on its website. Explain that you suspect a SIM swap and ask them to block online banking, cards and payments while it is sorted out. If you bank with more than one bank, call each one.
3. Take back your email. From a computer or tablet on Wi-Fi, change the password of your main email account: it is the key to resetting every other account. Sign out of all sessions and check that no automatic forwarding or new recovery number has been added.
4. Check your transactions. Log in to online banking (if you still can) or ask the bank for recent payments, new beneficiaries, virtual cards and linked devices. Screenshot anything you do not recognise.
5. Warn your contacts. If they took your WhatsApp, they may ask your family for money pretending to be you. A message from another account or a phone call is enough: "My number has been stolen, if I message you asking for money, it's not me."
6. Keep the evidence. Note the time you lost signal, screenshot the alert SMSs and emails, and write down the names of the people you spoke to at the network and the bank.

Do not wait to "see if the signal comes back". Every minute the criminal controls your number is a minute in which they can receive OTPs.

What if money has already been taken?

It is not your fault: this fraud exploits weaknesses in identity checks that do not depend on you.

1. Ask your bank in writing to record the transactions as fraudulent and to investigate a refund. The sooner you report them, the better.
2. Open a case at your nearest police station (SAPS) with all your evidence: the time you lost signal, the alerts you received, the bank transactions and the network's confirmation that a SIM swap was done. Ask for the case number; your bank and network will want it.
3. Complain to your network for doing the swap without properly checking your identity. Ask them in writing for details of when, where and how it was requested. If they do not resolve your complaint, you can escalate it to ICASA, the communications regulator.
4. Protect your identity. If they used your ID number, apply for protective registration with the Southern African Fraud Prevention Service (SAFPS), so that its member organisations take extra care with applications in your name.
5. If your bank does not resolve your complaint, you can take it to the National Financial Ombud Scheme.

If you feel in danger or someone is threatening you, call 10111, or 112 from a cellphone. You will find more about getting money back on our blog.

How do I stop it happening again?

• Do not rely on SMS OTPs alone when there is an alternative: in-app approval in your banking app, an authenticator app or a security key does not depend on your SIM.
• Set a SIM PIN and ask your network whether you can add a password or extra verification for changes to your number.
• Never share personal details, passwords or OTPs by phone or SMS, even if it looks like your bank. Your bank will never ask you for codes or passwords. If in doubt, read how to check whether a call or SMS from your bank is real.
• Switch on notifications from your bank and email so you hear about any change instantly.
• An app like NoCall helps you spot the fraudulent SMSs and calls these attacks usually start with, before you hand over your details.

Frequently asked questions

Could it just be a network outage? Yes. Outages happen, especially during load shedding. But if you are somewhere you normally have signal, other people on the same network have service, and you are also getting alerts about changes to your accounts, treat it as fraud until your network tells you otherwise. Calling to check takes five minutes.

Will I get my number back? Yes. The network can cancel the fraudulent SIM and issue a new one to you after checking your identity. Your number is still yours.

I have an eSIM. Can this happen to me too? Yes. The fraud can consist of activating an eSIM on another device. The signs and the steps are the same.

What about WhatsApp? Once your number is back, register WhatsApp again: the code will come to you and the criminal will lose access. Then switch on two-step verification with a PIN.

In short

If you suddenly lose signal with no explanation, act as if it is a SIM swap: call your network and your bank's fraud line from another phone, take back your email, warn your contacts, keep evidence and open a case. If a number that contacted you earlier asking for details looks suspicious, report it in the NoCall spam numbers directory: it could be the first piece of this fraud for the next person.