You should be able to find your owner's manual online by using the manufacturer and model number. That's what I would refer to.
Generally speaking, I would open the outside vent and make sure that the AC power cord from the fridge is actually plugged into the outlet inside of the compartment. Next, I would check the AC breaker panel inside of the coach to make sure the breakers are properly engaged. I like to turn them off and then firmly move the switch back to the ON position. If those simple things are not the culprit, I would refer to the troubleshooting in the manual. If you are not the only owner, it is also possible that a previous owner changed the wiring, for example, they may have had the fridge outlet or the circuit that the fridge is on wired to work off of an inverter instead of shore power.
Good luck fridge.
2005 22' BT Cruiser 5211, Chevrolet 3500 chassis w/6.0L Vortec V-8; 6'x12' Cargo Trailer; Honda CB500X motorcycle for street and ADV riding; Yamaha TW200 motorcycle for dual-sport and trail riding...All of it for fun and adventure!