@Kevin_Z Hello, thank you for the quick reply. I will assume the LED's indications are as follows: power, 3G/4G signal, wi-fi signal, unknown (irrelevant) When it stops only the power and wi-fi...

After initial setup the device recognises the 3G/4G modem but after a moment it's status in "Internet > 3G/4G USB Modem:" goes to Unknown. When I unplug the USB modem and plug it back in the router...