I'd bet you have something queued to the printer.
Do these:
(1) from maintenance commands enter "cu". When programming comes up do esc q until you get back to maintenance.
(2) in maint type "where". If the plane doesn't have a '*' next to it then you need to switch planes.
(3) in maint type "show print all" see if you have something queued to print. If yes, cancel it.
Ralph