Unauthorized debit of R2 400 from my account

Although I paid my membership in full for a family of 4 during a promotion, in March 2014, they decided to ********ly debit my account with R2 400 in May 2014. Upon enquiry I was first told, by the accounts lady at the branch, that there was an unallocated amount for the balance& the money will be refunded after I produce proof of payment. I did so, yet no refund. I've been dealing with this issue for over a year, the branch keeps on changing managers every few months and obviously no handover of such matters is done as each new manager is never aware of the issue, meaning I have to start over, submit all documentation, with the promise of it being resolved yet nothing. I want my money back. I will not be renewing my membership at this gym and wouldn't recommend Planet fitness to anyone, their service sucks, and they're *******!