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PUK and SIM errors can keep you from making calls or sending messages.

'PUK Lock' or 'SIM Lock' errors

If a SIM PIN security code has been entered incorrectly multiple times, the SIM will lock and require you to enter a PUK code to use your device again.

  • Be careful!
    • If you incorrectly enter your PUK code 10 times, your SIM will need to be replaced.
    • Moving your SIM to another device will not fix this error.
  • The PUK is unique to your SIM card. To get the code, you need to either:
    • Contact us online or with another phone. For your security, you must be the account holder or authorized user to verify.
    • Use the PUK Code printed on the card your SIM came in. Make sure the SIM card number matches the card.
  • Once you have the PUK code, follow the unlock instructions to enter it.

Other SIM errors

  • 'Contact your service provider'
  • 'Insert SIM' or 'Invalid SIM'
  • 'Unregistered SIM'

If you receive any of these errors, follow these steps:

  1. If using a non-T-Mobile device, make sure the device is unlocked. Contact the original provider if you need help.
  2. Turn off the device and remove the SIM. For steps to remove the SIM, check the Device page for steps.
  3. Re-insert the SIM card snugly in the SIM slot, then turn on the device. If you're able to register on our network, the error should no longer appear.
  4. Perform a manual network selection and try to register on the T-Mobile network.
  5. If available, move the SIM card to another T-Mobile device and test to check if it works. This test will help us diagnose the problem.
  6. If the error continues, use another device or online option to contact us.

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