Fuel Filler Cap

Hi, the fuel filler flap on my Santa Fe no longer responds to the trigger on the door armrest being pulled. At the moment I cannot determine if the faults lays with the trigger or with the solenoid actuator at the rear. Has anyone had similar problems and how did they cure it? I tried to lever the trigger from the door trim to test for power but without doing damage to the trim no way was it coming out. Any advice would be welcome.

Bob