If you have the Dometic model with water in the door, check that there's water coming out when you press the dispenser. If no water there either, and if you bought the trailer recently, the water may be cut off where the poly tubing is teed into the PEX, usually in the basement. If so, you'll have to take down the rear wall of the pass through basement storage to locate the cutoff.
If the water dispenser in the front of the refrigerator is working, you may have an electrical problem. Remove the lower vent panel on the outside wall behind the refrigerator. Check that both 120V outlets have power. If yes, locate the fuses on the circuit board on the back of the refrigerator and check that they're not blown. IIRC there are 2 fuses on the board and 1 inline fuse inside a wire bundle.