I have changed my 2 gang dimmer switch in my bedroom for a leading edge one which is better as there is no buzzing noise. There are 2 lights in my bedroom and two 2 gang light switches. The 2 gang dimmer is next to the door on the wall and the other standard 2 gang switch is next to the bed on the wall. The problem is, now that I have wired up the new dimmer, when I turn the lights off next to the bed by the switch on the wall, the dimmer switch next to the door doesnt turn on of off. When I switch the bedroom lights on by the bed the dimmer switch can turn on and off. There are 8 wires behind the dimmer switch 2 red, 2 blue and 2 yellow, and 2 yellow and brown in one sleeve. I put the blue wires in L1, the yellow in L2 and the red in the x symbol and the earth in the screw in the metal box. What have I done wrong?