To disconnect a User, you will need to log into the Cloud RDP server.
Right Click in the taskbar and select Task Manager
At the top, you will select USERS
Locate the User, and select the > symbol next to their login
Locate ES in the list and highlight it
In the bottom right corner of that screen, you will see a button that says "Disconnect" or "End Task" - click there.
That will end the session and the user will be able to log in again