Over Billing

I visited your establishment in Parktown on Friday 09 October 2015. We had food and drinks with my sister after we had checked the menu we then got the bill which was actually billed higher than what was on the menu. This actually meant I was charged more on the bill than what was on the menu. Now what worries me is how many people are being over charged when visiting your establishment. I tried raising this with the waiter and all I got was a 'sorry''. I would like to find out how I will get my money back as I had paid the whole amount with no assistance from your staff at the branch.