Incorrect amount debited from credit card

We recently booked a ticket from JHB to Durban.The website indicated that 12000 Voyager miles would be used and that we were liable for an amount of R169. After inserting credit card details, imagine our horror when NO miles were used and the full amount of R1199 was deducted. The call-centres (both SAA and Voyager ) took forever and ever to answer their phones and both were spectacularly unhelpful. We feel so ripped-off and manipulated! To add insult to injury, the equivalent flight from kulula is significantly cheaper and usually our first choice but we wanted to use up the voyager miles