New Sonos 2 App - cant add Sonos One device

I Want to setup a Sonos one in a new room on my system

Sonos One (flashing green after reset) shows in Sonos 1 app
Sonos 1 app launches new Sonos 2 app
New Sonos 2 app recognises existing Rooms and devices in that room
But not Sonos One

But New Sonos 2 app doesnt continue setting up Sonos One - Sonos One flashing green
New Sonos 2 app will not allow any new speaker / component to be added nothing happens when I make this selection