Gym company ****

They're involved in a money making ****. They invited me for a free gym for a month to try out and see if I'd like to join them. I was adviced I can cancel anytime. It was supposed to be a promotion that comes with a 3 year contract starting end of September. I came to cancel shortly after accepting the promo only to find out that I must pay a cancellation fee of R1433.00. Mind me I never even took a single class. They are adamant that I must pay for cancellation. This is ****************.