There should be three phillips or 10mm bolts holding the lamp on. You'll
need to remove a small plastic piece away from the trim panel under the
lamp to access the bolts. After removing the lamp, you'll need to remove
the four or five Phillips screws and disassemble it.
Once apart, check the tightness of the ground wire screw. Often, the
connection gets hot and melts the plastic, causing the connection to be
loose. I usually resolve this by removing the screw and transferring the
ground wire on top of the socket flange.