2 Months and no Refund

It's been almost 2 months now and I'm still waiting for MTN to refund me with the amount of R632.04! I keep getting the same old story that my query was forwarded to the relevant department with a reference number but as soon I'm done with MTN on the phone, the reference number gets closed. I am GATVOL of calling MTN on a daily basis, getting the same old story!! How long does a simple refund take?