From this case of specific account that have double listed to other account as it logged to other devices, then the first step that you need to do is by access the work emails/ other emails first that you have logged before. For this step, you need to sign in into device use personal gmail account in your phone and then use browser for open work account. It is requires browser for android device manager remove device step as it will send any notification when email is received into work account. You can do with any browser include firefox. Install the X-notifier lite add on for receiving notification. Snapshot to left that show the adds on in the Firefox menu and the on the right screen to notification appear in the tray. The verification from Gmail account will send email to your personal email and it will notify into notification tray.
There are couple of Gmail adds on that you also able to use, but it is not installed. The X-notifier lite add on is basic notification. After you finish the step, then the account you remove will not add to any Play store or listed in the account setting as the specific account has logged before. In the other case when you know that device you not recognize because your friend borrow your friend to logged into their account and it has been listed to your account, then you can do this step. First is use the phone browser and then go to “myaccount.google.com”. In section of “sign-in and security” option tap the device activity and notification. In this box, see to the section of “recently used device” section and go to “review devices”. You will see the list where there is devices you have been use for logged on or your friend use and then click “remove” for remove device. This will sync to android device manager remove device that will also remove device from your Google account.