This indicates that the micro SIM card is locked.
To unlock the SIM card, log in to the web UI and enter the PIN code or PUK code. To obtain the PUK code, contact your internet service provider.
Note: If the PIN code is entered incorrectly 3 times, you will be required to enter the PUK code. If the PUK code is entered incorrectly 10 times, the micro SIM card will be locked permanently.