Last checked: 26 June 2026
If your SIM swap is not working, do not keep retrying the same request blindly. A failed SIM swap can happen because the wrong network route was used, the new SIM is not active yet, the USSD session timed out, the account failed security checks, or the provider requires customer care, WhatsApp, an app, or in-store help instead.
Start with the quick checks below, then move to the provider-specific route for your network. If your SIM swap was completed but your phone has no network, read no signal after SIM swap. If you need the normal process first, read how to do SIM swap South Africa. For direct help routes, use mobile network customer care numbers.
Quick Fixes to Try First
| Check | Why it matters | What to do |
|---|---|---|
| Confirm the network | SIM swap routes differ between Vodacom, MTN, Cell C, and Telkom | Use the route for the provider that owns the number |
| Check the new SIM | Some swaps must be started from the replacement SIM | Insert the new SIM, restart the phone, and check for signal |
| Confirm RICA or activation status | A new SIM may not work if it has not been registered or activated correctly | Check the starter pack, registration step, or provider instructions |
| Check signal strength | USSD can fail when signal is weak or unstable | Move to stronger signal and retry once |
| Wait for activation | Some SIM swaps are not instant | Wait for the provider’s confirmation or stated activation window |
| Stop after repeated errors | Failed security checks or duplicate attempts may delay the process | Contact customer care instead of guessing |
A successful SIM swap should usually end with a confirmation message, a clear instruction to wait, or the old SIM losing service while the new SIM begins to connect. If you see repeated messages such as “request failed”, “service unavailable”, “session timed out”, “invalid request”, or “SIM swap not allowed”, stop and use the official support route.
Why This USSD Problem Happens
You used the wrong network route
A SIM swap keeps the same number on a replacement SIM from the same network. If the new SIM belongs to another network, you may be trying to port the number instead of doing a SIM swap.
Before retrying, check that:
- the new SIM is from the same provider as the number;
- the old number is still active or recoverable;
- the new SIM has been bought and prepared according to the provider’s instructions;
- you are not confusing SIM swap with number porting.
The SIM swap code may be wrong or outdated
A SIM swap code not working problem often happens when an old USSD code or menu path is being used. Networks can change their menus, and some SIM swap requests may be handled through customer care, stores, apps, or WhatsApp instead of a simple USSD flow.
For MTN, the official help page says users should buy and activate a new SIM, then dial *135*3# on the new SIM to start the SIM swap process. (MTN)
For Vodacom prepaid SIM swaps, Vodacom’s guidance says users should buy a new prepaid starter pack, register it for RICA, dial 135 from the new SIM, choose the option to use the old cellphone number, and then follow the consultant-led process. (VodacomNow)
The new SIM is not ready yet
A new SIM may need registration, activation, or network provisioning before it can complete a SIM swap. If the phone says “No SIM”, “Emergency calls only”, “No service”, or does not open USSD menus, the SIM swap request may fail before the provider can process it.
Try this:
- Insert the new SIM properly.
- Restart the phone.
- Wait a few minutes for network registration.
- Check whether basic USSD menus open.
- Try the official SIM swap route once more.
- Stop if the same error repeats.
If the phone still has no signal after the swap, use no signal after SIM swap.
The account failed security checks
SIM swaps are protected because they can be used for fraud. A provider may block or delay a SIM swap if the account details do not match, the answers to security questions are wrong, the number was recently reported lost or stolen, or there is unusual activity on the account.
Do not guess security answers repeatedly. If you fail verification, contact the provider through its official customer care channel or visit a store with your identification and SIM details.
The request was submitted but not activated
Sometimes the SIM swap request is accepted, but the SIM swap is not activated yet. During this period, the old SIM may still work, the new SIM may show limited service, or both SIMs may behave inconsistently.
Vodacom states that prepaid SIM swaps are processed immediately but may take up to 3 hours for the new SIM card to activate. (VodacomNow) Cell C’s FAQ says users should wait at least 2 hours before inserting the new SIM card after following the SIM swap route for a lost, stolen, or damaged SIM. (Cell C)
Provider-Specific Checks
Vodacom SIM swap not working
For Vodacom prepaid, check that you bought a new prepaid starter pack, completed RICA, inserted the new SIM, and dialled 135 from the new SIM. Vodacom says users should select the option to use the old cellphone number and will be routed to a call centre consultant for the SIM swap. (VodacomNow)
If the Vodacom SIM swap still does not work:
- check that you are using the new SIM;
- confirm the starter pack was RICA’d;
- wait for the activation window;
- restart the phone;
- contact Vodacom if the request fails or you receive a SIM swap alert you did not request.
Vodacom warns that SIM swap fraud can give criminals control of a user’s phone number and access to OTPs, and says users should contact Vodacom if they receive a SIM swap SMS they did not request. (VodacomNow)
MTN SIM swap not working
For MTN, first check that the new SIM has been bought and activated. MTN’s official help page says to dial *135*3# on the new SIM to start the SIM swap process. (MTN)
If the MTN SIM swap code is not working:
- make sure the new SIM is active;
- check that you are dialling from the replacement SIM;
- confirm the number is still available for SIM swap;
- try again only once if the first USSD session timed out;
- contact MTN or visit an MTN store if the code keeps failing.
MTN also states that SIM swaps can be processed at any MTN store. (MTN)
Cell C SIM swap not working
Cell C’s support FAQ says that if a SIM card has been lost, stolen, or damaged, users can buy a new Cell C starter pack and use Self-Service IVR, go to a Cell C store, or speak to an agent. The FAQ lists Self-Service IVR on 084135 from a landline or another cellphone, Cell C stores, and 084135 or 135 with the option to speak to an agent. (Cell C)
If the Cell C SIM swap is not working:
- check whether you have an active Self-Service PIN;
- confirm you followed the route for a lost, stolen, or damaged SIM;
- wait at least 2 hours before inserting the new SIM if instructed;
- use a Cell C store or agent if the IVR route fails;
- do not keep retrying if you cannot pass verification.
Telkom SIM swap not working
Telkom says SIM swaps can be done through its WhatsApp self-service channel by sending a WhatsApp to 081 160 1700and following the prompts. Telkom also notes that SIM swaps through Telkom stores are charged for. (Telkom)
If the Telkom SIM swap is not working:
- check that you are using the official Telkom WhatsApp route;
- follow the prompts carefully;
- confirm that the number and SIM details are correct;
- use Telkom support or a Telkom store if the WhatsApp route fails;
- check the fee before choosing an in-store SIM swap.
When to Use an App, Website, or Customer Care Instead
Use an app, website, WhatsApp channel, customer care, or a store instead of USSD when the problem involves verification, account access, possible fraud, or repeated technical failure.
Use another official channel if:
- the USSD menu keeps timing out;
- the SIM swap code does not open;
- you failed security questions;
- the new SIM has no signal;
- your old SIM suddenly stopped working without your request;
- you received a SIM swap warning you did not authorise;
- the provider says the request is blocked or pending;
- the swap has not activated after the expected waiting period.
Prepare these details before contacting support
Have these ready before you call, WhatsApp, use the app, or visit a store:
- the cellphone number you want to keep;
- your ID or passport details;
- the new SIM pack or SIM serial number;
- whether the old SIM is lost, stolen, damaged, or still available;
- the date and time you tried the SIM swap;
- the exact error message;
- any confirmation SMS or warning SMS;
- proof that the SIM was registered or RICA’d, where required.
Do not share your banking PIN, banking app password, card PIN, email password, or one-time banking password with anyone claiming to help with a SIM swap.
What you should see next
After a successful SIM swap request, you should normally see one of these outcomes:
- a confirmation message;
- an instruction to wait;
- a customer care verification step;
- the old SIM losing service;
- the new SIM connecting to the network;
- calls, SMS, and mobile data beginning to work on the new SIM.
If the swap completed but calls, SMS, or mobile data still do not work, the issue may no longer be the SIM swap request itself. It may be a signal, activation, APN, account, or device issue. Use no signal after SIM swap for that next step.
Retry Safely
Only retry the SIM swap request if the first attempt clearly failed because of signal, timing, or a session timeout.
A safe retry looks like this:
- Restart the phone.
- Move to a place with better signal.
- Confirm the new SIM is inserted.
- Dial the verified provider route once.
- Follow the prompts slowly.
- Wait for the confirmation message.
- Stop if the same error appears again.
Do not keep retrying if the process asks for security answers you are unsure about. Do not use unofficial agents, social media inboxes, or websites that ask for sensitive personal information.
Escalation Route
Use this route when the SIM swap still does not work:
- Check the correct provider guide.
- Retry once only if the issue was a timeout.
- Wait for the stated activation window.
- Restart the phone.
- Test calls, SMS, and mobile data.
- Contact the provider through official customer care.
- Visit a store if identity verification is required.
- Contact your bank immediately if you suspect SIM swap fraud or unauthorised access.
For direct provider help, open mobile network customer care numbers.
FAQs
Why is SIM swap not working happening?
SIM swap not working usually happens because the wrong network route was used, the new SIM is not active, the USSD session timed out, security checks failed, the account is restricted, or the provider requires customer care or in-store verification.
Does this mean the SIM swap code has changed?
Possibly. SIM swap codes and menu paths can change. Always check the provider’s current support page before using an exact code, especially if an old USSD code no longer opens the correct menu.
Can I fix it without calling customer care?
Sometimes. If the issue is weak signal, a timed-out USSD session, a phone restart, or waiting for activation, you may be able to fix it yourself. If the issue involves failed security checks, fraud warnings, a lost or stolen SIM, or repeated errors, use official customer care.
Should I use the app instead of USSD?
Use the provider’s app, website, WhatsApp channel, or store if USSD keeps failing or the provider officially supports that route. Assisted channels are often better when identity checks, account restrictions, or fraud warnings are involved.
Can retrying the USSD request cause extra charges?
Fees and USSD costs depend on the provider and the type of request, so check the provider’s current terms before assuming it is free. The bigger risk is repeated failed verification or duplicate requests, so retry only once if the first failure was a normal timeout.
How should I report SIM swap not working safely?
Report it through your provider’s official customer care number, app, website, WhatsApp channel, or store. Give the error message, time of the attempt, SIM details, and whether the old SIM is lost, stolen, damaged, or still available. Never give banking passwords or OTPs to someone who contacts you about the SIM swap.
Which related guide should I read next?
Read how to do SIM swap South Africa if you need the normal SIM swap process. Read no signal after SIM swap if the swap completed but the phone has no network. Use mobile network customer care numbers if you need the official support route for your provider.
