User 99999999 is not able to print more than 500 pages, how to resolve?

The 500 pages is the default volume limitation.

This limit is NOT applied if all three are set:
  (a) "Machine action when limit is reached",
  (b) "Tracking Permission"
  (c) "Stop Printing".  (Last two are under "Enhanced Print Volume Use Limitation". )

When all three are set, the limit is controlled by the tracking application.