Hi Richard,
What is the switch model? Run a "show multi-auth session" command for the port in question and see if there is a session for the device/user in question. It would be odd that the switch apply a session for some users and apply that policy but not other users if the same RADIUS server sent the same Filter-Id in both cases. In the show multi-auth session output there should be a PID number that matches the policy name up, as seen in the output of the "show policy profile all" command. If the PID is incorrect or missing for the session/user in question but is accurate/present with other sessions that have the same policy name, then you should probably call in and open a case with the GTAC's Switching group to see what's going on there.
Regards,
Scott Keene