The answer to 'why is my dimmer switch not working' is that there are several common causes, including a faulty dimmer switch, improper wiring, or issues with the light bulb or fixture. Symptoms may include the switch not turning the lights on or off, flickering lights, or the lights not dimming properly.
Some common solutions include replacing the dimmer switch, checking the wiring connections, and ensuring the light bulb is compatible with the dimmer. However, if you're not comfortable working with electrical components, it's best to call a licensed electrician to diagnose and resolve the issue safely.