Cancelation taking over 2 months, account running high, no indication of a refund

I submitted a cancelation in early April , no acknowledgement was ever received. The only thing I keep receiving are payment reminders and account statements. When I call to follow up, I get sent from pillar to post. I honestly feel they are dragging the process in order for the account to be due again, consequently total due is now over R6000. They will not say if they will write this debt off nor refund my R5000 deposit.