If your output is correct, users have to login after 5 minutes of inactivity, not 90 minutes. I am not sure if you have something else going on.
To change it to 90 minutes, you would change this parameter (in seconds):
(Aruba7005-US) (config) #configure t
Enter Configuration commands, one per line. End with CNTL/Z
(Aruba7005-US) (config) #aaa timers idle-timeout ?
<1-15300> User idle timeout value. Valid range is 30-15300
seconds in multiples of 30 seconds or 1-255 minutes.
Default is 300 seconds