Hi - the stock plusnet router doesn't work with BQM, due to the security restrictions on the router. You need another device on your network to respond to the pings from BQM on behalf of the router.
The solution I've used is to put a firestick (any always on wifi device will do) into a 'DMZ'. It's simple to find the DMZ setting and chose the device in the router settings, then it works.
You should understand the security implications of doing this before doing so, and once you've collected the data you want, turn the DMZ back off.