Removing Devices?

I have a smartthings outlet I got with my kit last year. I need to remove it from ST and Google Home so I can set it up again somewhere else for a different reason. I think I have it removed from ST but in GH app it lists the device under SmartThings/Samsung Connect. Di I do something wrong when I tried to remove it in ST?

thanks Robin.

I have looked and looked in the app and I don’t see where to update the authorized list. I remember it from when I set things up but obviously I’m overlooking it.