To remove the bulb; push inward and rotate CCW a few degrees. Since they can be stubborn to remove, try pushing inward and
wiggle it to break any bonding from corrosion.
If the bulb breaks, you can always collapse the base with needle nose pliers and dig it out of the socket. Coat the new bulb base and contacts with dielectric grease before installation. This should minimize the problem in the future.
Tom D.