Daylight ******* with no shame!

This company should be closed for *****! I had an account with Planet Fitness that was handed over to them. When I started my payments in June the amount was just above R2000 now they are telling me the amount is R3200 because of interests and calls that they make to me, unnecessary calls for that matter! I have been sending proof of payments every month but nothing gets resolved, the email *** that they use never responds. I make my payments every month but the amount keeps going up instead of going down. Now they're trying to convince me to settle and get a discount! I think this is what they do, frustrate you so you can settle. I have requested my statement but up to now no response! Is it even legal to do this to consumers!