If there is no power arriving at the bulb then it is a fuse or wiring fault. If there is power, te bulb is OK abut does not come on then the switch in the latch or the wiring leading to it is at fault. The switch in the latch provides a ground to turn on the light. Have a look at the latch, the switch is a blade which wipes on a brass boss fitted to the latch claw.
Open ur boot and take the plastic cover off the latch.. U'll see a flap of metal that will be touching the latch mechanism.. This completes the circuit and turns the light on.. That's the switch.. If it's not touching or, quite common, the strip of metal has broken off, then that's ur prob..