Demio's security measures ensure that two Users cannot log in to the same account using the same password. If a new User access the account with the same login information, a User interface warning will pop up indicating that the prior User has been logged out due to another User's activity (logging in):
The best way to ensure every person that needs to access Demio can do so would be to add them as Team Members.
This would allow them to log in with their own credentials and access Demio from their own account while still being able to interact with the activity of the main Demio account holder.
Here is exactly how to set up those Team Member accounts!