How do I fix my car aerial?

Its for a Mazda 1998 car, the aerial is either stuck or the motor doesn't work, but the motor does make a whirring noise when I turn the key in the ignition. Have tried pulling the aerial out but it won't budge, and can't find the box where all the motor would be. I can only see one large panel to take off rather than just a little one, any ideas? Used WD40 already to no effect