Fan works but light is not. I changed the light bulb and still nothing. I decided to replace the fan with another working one from another room, but still the light on the replacement fan is not working. The replacement fan has 2 black and 2 blue wires, 1 white and green.
I connected 1 black and blue to the black from the ceiling and white to white and green to bare ground wire from the ceiling. I capped the extra black and blue from the fan because I will not require the additional lights.
I'm afraid to connect the extra black and blue together with the already connected black and blue with black on the ceiling. Please advise

Sounds like you are not wiring these fans right if the light isn't working on either fan.

What make/model fans are they? Do they have remotes?

Ceiling Fan Wiring, Ceiling Fan Wiring Technical Help, Do it Yourself (DIY) - Ceiling Fans N More

Hampton bay and no remotes

So are you saying that the fan has 2 blacks and 2 blues coming off the rod?

Yes (probably because the fan has lights above the blades and lights below the blades). I removed the lights above the blades and only want to use the lights below the blades.

Trace the blue wire from the lights back up to the ceiling and make sure it is connected.