Hi, trying to change an old dimmer switch for my bedroom light. The button is missing so I bought a 1-way white plastic fitting.
When I tried to replace the old one it was different inside. It had 3 wires going into it (black, blue and earth). My new one only had places to fit 2 wires and in the instructions it says to connect the earth to the box fitting or something. There doesn't seem to be anywhere on the box to fit the earth though.
What do I need to do?