Lies and *****s

I went to Virgin active to enquire about their prices. When a got there a consultant offered me a free trail and she said I should pay a trail fee of R50.

I went there for a day and told her I cannot join due to their price being too high. The following month on the 1st the debited R680 from my account which I reversed. Since then I have been calling then asking ro cancel my membership, but instead they require me to pay a fee of R2 000.

Why should I pay such a fee while I never joined?