Help Center

If your phone displays a SIM Card error message, do a couple of quick checks.

Firstly, ensure that you have inserted the Tello SIM into a compatible device - use our device checker to confirm this.
Secondly, ensure that your phone is unlocked. Contact the previous phone carrier (or phone seller) to confirm this. A locked device will not be able to use the Tello SIM.

Once you have confirmed the above, follow these steps:

• Turn your phone off.
• Remove the SIM Card.
• Make sure the SIM Card isn’t damaged or you’ll need a replacement.
• Insert the SIM Card back into your phone.
• Turn your phone back on, follow any on-screen steps provided and your phone should start to automatically activate the Tello service.

Here’s a quick list of some of the most common SIM Card errors you may run into:

• "sim not supported"
• "network lock,"
• "network unlock pin,"
• "unsupported sim"
• "SIM Lock"
• "SIM Invalid"
• "Network Lock"
• "SIM Not Supported"

If you receive any of these error messages, your previous carrier may have enabled a lock or restriction to your phone and you will have to reach out to them to remove this lock.