I have a 1 way 2 gang switch in the kitchen operating 2 lights but one of the light is not working. I have tried and replace the bulb holder but it still doesn't work. I have even try and replace the wall switch and still it doesn't work . And secondly, I am trying to replace a normal switch with a dimmer. When I remove the old switch, I noticed that they are 3 main cables(grey) entering the switch, the earths and neutrals(black) are all blocked and the 3 remaining red wires are connected as follows: 2 to l2and 1 to L1. The dimmer switch that I bought have 2 connectors, one L and the other is a wavy line with an arrow through it forming a X. Which wire goes in where?