@Mimi12 

Thanks for posting question here:

If you are experiencing the issue of "No SIM card detected" on your 4G LTE Router, you can follow these steps for troubleshooting:

    1. Check if the SIM card is inserted correctly and firmly in the SIM card slot. Different models may have different slot sizes, such as Micro SIM or Nano SIM. Please refer to this FAQ on how to insert the SIM card correctly: https://www.tp-link.com/support/faq/3196/

    2. Restart the 4G LTE Router with the SIM card still inserted in it. After the device restarts, check the SIM card status again on the Advanced->Status page.

    3. Test the SIM card on another device to see if the SIM card itself is functioning properly.

    4. Try a different SIM card. (It seems you have tried this)

    5. Perform a factory reset: Hold the reset button for about 10 seconds until the power LED starts flashing.

If none of the previous steps solve the issue, please contact TP-Link local support with the information mentioned in the FAQ: What should I do if my TP-Link 4G LTE Router cannot detect SIM card?