Cell C doesn't pay their debts

I am a long standing Cell C Customer. I decided in May to cancel my 2 data lines as I no longer needed it. I was given information via sms by the call centre agent of the outstanding balances etc. I made the payments, but the one data line was already cancelled the previous month so which means I overpaid that account. So a refund of R668.74 is due to me from Cell C. I have been speaking and calling Cell C agents since beginning June. I sent an email with my complaint to Cell C customer service. Up until 2 days ago, I'm still receiving sms' to say that my "query is received and will be attended to shortly". However when I call Cell C to follow up, I get sent from post to pillar and nobody can give me the correct information in regards to when my refund will be done. Cell C is so quick to send sms' and say that they will suspend your line if you don't settle your account, but when they owe the customer money, then there is a delay or no-one can answer for the errors they make.

I am frustrated and would like feedback in regards to my complaint. I would like to speak to a manager and not a call centre agent, because none of the agents that I have spoken to in the past month and a half has been able to assist me. I would like my refund to be done before the end of business, on Friday 06 July. I am tired of waiting so long for my money.