Answer
Sometimes you can get a series of network state 0 and 2; in that case it means the modem cannot find any network to join:
- Network state 0 (Not Registered) means the modem is idle.
- Network state 2 (Searching) means the modem is searching for a network.
When a modem finds and joins a network, it issues network state such as 1(Registered, Home Network) or 5 (Registered, Roaming).
A network state 3 (Registration Denied) means either the network selected is incorrect for the IoT SIM Card, or the SIM is inactive/disabled.