Classic ST app, phantom device

I don’t know exactly how I did this. But I think I asked the app to search for devices and it found (at least) one Philips Hue light which had already been found and named. Now I have two Philips Hue light things, one with the old name: “Sofa” which the app can turn on and off but nothing happens, and a new one called “Philips Hue White” which also works in the app and turns on and off the light previously known as “sofa”. And there’s no delete “thing” anywhere…

open the device, click on the cog in the upper right of the screen and you will see the remove button.