Headlamp not working, light on dash informing you that service required.
First check fuse F43 in engine bay fuse panel as this may have blown due to the fault.
The actual fault is the bulb connector and ford have made a replacement (connector kit part number-1 766 617) that can be easily fitted by anyone with a little technical knowledge.
At this point you may as well change the bulb at the same time.
This problem is known on all models of ford focus from July 2011 onwards.