3 ft fiber optic tree that the color wheel will turn but it is not lighting you opened the base and there are no bulbs to change or loose wires Any suggestions?

I own a 4' Fiber Optic Tree. Inside the base, at the bottom, center, is a one piece light and refractor. 2 screws hold light down. Light is approx. 1 1/2" wide. I bought a replacement bulb at the Home Depot. Bulb 20watt,22va,60hz. Good Luck.