May I ask what kind of sonos device it is, and if it is a rather new or an old one? (model type)
If only the IP address gets listed with the generic name "Sonos", it means that it found the device during a network scan, but communication with it later failed.
I guess you have tried to log out from your Sonos account and log back in again (in case your access token for some reason has become invalid)? Also tried to reboot your flic hub?
Could you please give me the text output that you can see in a browser if you go to http://sonos-ip-address:1400/info ?