@Anko_Wolf At least it was a simple fix in the grand scheme of things!

If my assumption for the S20 is correct, then both devices are using Android 10. This is likely to be an incompatibility with it in the app.

@Kayfersmum Hi, With Sky Fibre, you'll be using BT Openreach's Fibre 'VDSL' standards (Not Virgin's DOCSIS) so any router/modem you select will require compatibility with this system. I haven't been...

Did you add your ISP's connection username and password?

I'd give the Device Mode "Modem Only" a go first, unless you specifically need the router to do DHCP, etc rather than the Decos.

daemon.err nrd[17800]: estimatorCmnHandleBeaconReportEvent: Invalid beacon report for 5E:6A:E6:8F:4B:95 This normally means the device is out of useful Wifi range of the Deco.