Cancel swim clases once received payment

My Son took part in swimming classes at Making Waves, and these guys are so greedy, that they fill the class to the brim. The class is only 30 min long, and they only spend about ten min to train your child to swim. I decided to cancel the class, but then I was threatened with lawyers, as I had to give a month notice. I was told by Sarah (owner) that if I pay for the cancelation month, my child could take part in the classes, as I actually paid for it.<br> I made payment, and a week later I was advised that my child's time slot as taken, and that it becomes my problem, as they wont refund my money. Please stay away from this swim school in O riley merry str in Benoni, and they like to change their name all the time. They trainer is Nadine, with even a worst attitude.