If a sudden reboot of a router (Watchdog) occurs, the bootlog has to be read out for further analysis.
If a bootlog of a router with an integrated USB cellular modem shows the message MCP-Info: USB-Reinit in state WaitForUsbDevice (1) before the actual watchdog output, this has the following meaning:
The cellular modem isn't connected to the USB stack for 24 hours and the router tries to fix this issue via a daily reboot as a last resort. Therefore the cellular modem is not functional.
If the cellular modem is still not functional after a reboot, the device is defective. In this case please submit a repair request via the LANCOM website (if the router is still under warranty).