found_upnp”:true,“error”:“Did not find UPnP service with WANIPConnection on network”}
is often caused by incorrectly configured ports, such as a port number mismatch or the UPnP autoconfiguration not working. The latter seems to be common with BT Smarthub. See the suggestions in this Roon staff posts:
If this doesn’t help, I’m afraid we will need screenshots of your Smarthub settings