How do you know they are not?
Did any of them experience a crash that disconnected them?
Any chance the user closed the file but a link to that file re-opened it in a hidden window?
They aren't even in the building at the time. And it has been a different user each time.
Just exploring possible explanations.
User names are preference settings on specific installs of filemaker. It's always possible that another user has their preference set to the same user name. Any chance that this is the case?
Any chance that the user left the building with filemaker still running on their machine?
No, the user names are the people's first and last names and they are all accessing on laptops that they take with them.
Hmm, did they just sleep their lap top with filemaker still running and then leave the building?
What happens when you try to quit and click "Send message" to these phantom users?