Erase from the list the one which the noted last activity is earlier and keep the second, with later activity (that's the one currently working). Alternatively, you can remove both instances of the doubled device and reconnect it back, after.
Re: 1 of my 3 computers is showing twice and won't let me sign in the one that got disconnected
Well, we know it can be hard to keep up good habits, so we made a new working from home cheat sheet, with some good habits, some things to avoid and some tips for making your day a little easier. Check it out here.
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