Robertson Winery Passing The Buck

I purchased a box (3L) of the Robertson Winery Shiraz on 9 August. On opening and poring a glass I noticed it was a dull colour and when I tasted it I could tell it had already started to change and deteriorate. Wasn't pleasant. So on the 11th I wrote them an email. I got a response that it was being looked into and I needed to provide certain details off the box, which I did. On 20th I received a response. Firstly it said they can not replace the product as it was actually the responsibility of their logistics provider. They had sent my details on and Vinimark, the logistics guys, would contact me. Secondly they offered me 20% off my next purchase from their online store. Till today nothing from Vinimark. And they can take their 20% and keep it. If this is how the manufacturer deals with faulty product by passing it over to the delivery guy, NO THANKS! Won't buy their products again!