Try stopping and starting Grid Management Service (gabd) on the Grid Control Server. The service must be started by the root account in Unix operating systems.
/platform/lsf/gms/bin/gaadmin stop
/platform/lsf/gms/bin/gaadmin start
If that doesn't resolve the issue, provide additional information including:
What operating system(s) does the environment have?
What type of authentication is being used in the environment?
What user is logged into SAS Management Console when the behavior happens? Does it happen with all users or just certain users?