I installed a new 4 light bow spotlight bar but didnt take a note of the original wiring for the previous light. There were 2 main cables each with a red, black and earth wire. I connected the black wire from the switch to the live terminal on the light, the two red wires I wired together, the two earth wires together and into the earth terminal on the light and finally the remaining black wire to the Neutral on the light. I had an existing dimmer and it switches them on and off but won't dim them. I have the same light in another room and it worked on the existing dimmer in that room so not sure what has gone wrong here. Any advice would be greatfully received.