Lou Harvey damage

I purchases a Lou Harvey beach bag with great excitement as I had wanted one for a while. However my excitement turned to disappointment after using the bag four times at the beach. The bag grew black mould within the material. I stopped using it after a while as i was embarrassed to use it. Upon approaching Lou Harvey to perform an exchange I was told they would only offer me a 'small discount' on my next purchase as i had an old style bag. I was also told that the bag is not waterproof (which i am very well aware of) and the mould was grown due to not drying the bag out properly. I can personally testify that in the very few times i have used the said bag, i instantly hung it over the washing line to dry once I got home, which is something i do with ALL my beach bags and have never had this problem. I am disappointed that I spent over R1000 on a bag I only used four times and now to get it replaced I have to buy another one? I would have been happy with an exchange of the old style as I just want to use the bag without the embarrassment. One disgruntled client!