Golden Valley Casino Lodge

Last week (Aug, 25th) I've done a reservation for one night (on Aug, 26th) on the Golden Valley Casino Lodge. I had to cancel the reservation on the day of the check-in, due to family illness. After that, they charged me R983.00 on my credit card! On the policy cancellation, I can see: "You can cancel free of charge until 7 days before arrival. You'll be charged the total price if you cancel in the 7 days before arrival. Any cancellation or modification fees are determined by the property. Additional costs will be paid to the property." How can I cancel the reservation 'free of charges', if I haven't the 7 days?! I do not agree with the charge, and I do not recommend the Sun International to anyone.