First a single user can only log in to a single device at the same time, the solution is as follows:
1. select User>User Access
Policy>Access Service, click Modify icon

2. Change "Default Max. Devices for Single
Account" and "Default Max. Number of Online Endpoints" to 1

Then, we can also set that the first user
who logs in will not be kicked out by
the next logged in user, the
solution is as follows:
1.Select User>User Access
Policy>Service Parameters>System Setting>System Parameters, then click configure icon

2. change "Log off Duplicate
Account" Parameter to disable. Last A single user can only log in to a single device at the same time,
and then the first logged in user will not be kicked off by the next logged in
user
