Symptom
Max Sessions Counter time limit is not deleting the sessions older than the timer set.
Conditions
Do 5 authentications with different macs but same user, send accounting start for each one
In ISE under Administration-->Settings-->Max sessions, Configure the user limit to 3, in Counter time limit set to one day.
Do a new authentication from the same user and different mac from the other 5, this will fail as expected.
Change the Counter time limit to 15 minutes.
Wait 15-20 minutes and do a new authentication with same user and different mac, this one will fail.
The trigger is to have more active sessions than the counter you set in Max session per User. In this example, ISE had 5 authentications and Max counter was set to 3.
Workaround
Reload the PSN to clear the Max Session counter
