billed for terminated account

I opened an account with Telkom for a fixed line look alike that came with 10gb. After 3 days of persistently calling the customer care line, no one was able to help me either the line rang unanswered for 10-20min before automatically rejecting the call or the offices had closed. I subsequently terminated the contract and requested for a refund. I was told they had to reverse my application, a process which would take 2 weeks then only can they refund me another process which would take two weeks. so in total I'd need to wait one month. now one month later they debit my account for a line I do not have and I'm not using. I feel I've tolerated their incompetency for a while now and I am fed up. I've been waiting for a month for the refund and instead they taking money from me. This is totally unacceptable how do they take more than a month to fix this matter?