new golf cab. roof issue & warrantee not honored

My VW Golf 6 is still new and the roof is scuffing through with being opened and closed, I've reported this matter to VW SA and got told that this is a bad maintenance issue as I open my roof when the car is dirty and the dust causes the roof to scuff. I have a friend with exactly the same car and she is having exactly the same problem. I've now had the strings holding the canvas roof to the frame tear off the canvas and again VW say's their position on the matter will not change. Their advice is pay R20 000.00 for a new roof. Being a brand new car and not having the factory honour their guarantee is awful!!! will never in my life buy another VW ever as they don't honour their promises when something does go wrong.