Pay for an hour long manicure that lasts 39min

I booked a Power HOUR manicure at Sorbet Menlyn. I arrived on time for my appointment at 10am. I waited 12min for the nail technician to attend to me and my manicure was over by 10:51. At the end of the appointment, as I was paying, I commented that the appointment was shorter than the menu had promised and the response i got was \there wasn't much to do"... Whenever i book a manicure or pedicure I always book the \""Power Hour\"" option and have never been attended to for more than 50min. My hands and feet have always looked great when Iv walked out the door so it never bothered me or even occurred to me to complain"