Pot Holes damage my husbands Tyre and they refuse to pay for a new one

On Thursday the 28th April we went to your branch in Ottery Capr Town. It was raining that day and as we entered the parking lot my husband drove into a pot hole which was filled with water and he damage his tyre. We had spoken to management and they said that its the first time that this had happened however the parking security said that its not the first time and they had informed management and they did nothing about it. They then contacted my husband saying that they will not refund him for his tyre as there was a sign up to say parking at own risk. I expect a refund as they can not provide proper parking or even fix there parking lot. If we do not receive a phone call informing us that they will refund us i will post this on your Facebook page and will that the matter up with the CPA and will also send this post to the ombudsman. PLEASE CALL ME TODAY. YOU CAN NOT HOLD A CONSUMER LIABLE AS YOU CAN NOT FIX YOUR PARKING LOT.