when you pop the panel off there will be a strengthening plate where the lock is

the motor is tucked up behind here with a few screws and stuff so you need to unscrew it first, the it will unhook from the locking rod

the lock itself normally has an accumilation of dirt and possibly grit inside it which causes it to jam up, make sure you can take the plastic outer hnadle off to expose the shinet metal bits and clean both inside and outside surfaces

there are silicon type srapys you can use to give it a bit of a sliding hand