Fog lights melted

I have a polo 1.4 tsi (gti) my car recently went in to get my radiator replaced. Plane and simple after being done my fog lights weren't fitted correctly and melted the whole housing. Vw umhlanga does not want to own up to it. And still want me to pay for there mistakes , I'm fed up with there service . Around a year ago I had to change left headlamp bulb which burnt out and went to Vw to get it sorted out , I booked the car an had to wait 2 weeks to get it replaced eventually I got fed up and changed it myself, I don't know what to do anymore when it comes to Vw. Some advice would be nice.....(I've only dealt with Vw umhlanga because I bought my car from there)