I've a policy of my system, which is prevent multiple login. And I'm able to that by updating user's security stamp every time he/she logged in.
The following links are the method I used:
Prevent Multiple Login in ASP.NET Identity
CookieAuthenticationProvider and user session invalidation on change of SecurityStamp
The problem is I don't know how to display a message box to show to the user that is being force logged out.