Turn Signal not Working

Hi there,
Seems my left turn signal is not working in my duster, just the front one. Flashers are working OK, rear turn signal OK and both right side turn signals OK. When I put the left turn signal the indicator won't illuminate in the dashboard, just the rear lamp flashes. The bulb is not broken, the parking lights are working too. Where should I start looking to fix this issue? Any input is appreciatted.