Did you mean to say you unplugged "camect" rather than the "camera" ? Unplugging a camera isn't supposed to change anything related to activation.
If you have a Nest thermostat that's probably what's being detected as a "Nest device". Unless you're signed in to Nest we're unable to tell that it's a thermostat rather than a camera.
Since you know you don't have a Nest camera, the right fix is to disable it using the slider at the top left of the camera's title bar. Unfortunately though, there's currently a bug in the UI that may prevent you from disabling it -- Please put up with it for a while, and you'll be able to disable it after the next software update, which will hopefully be within a week or so.