Awaiting my refund to no avail

Can someone help addressing this mess with Cell C? They just need to close shop. I made a mistake to my Cell C account and an excessive amount of more than R36500 was paid into my cell C account. This money was intended to pay my school fees. I got hold of Cell C and they promised to refund after one day following the call. Now, I have missed my exams because I was suspended from school for non-payment s a result of this delay. Whenever I have called Cell C, someone tells me that customer service has no access to back office. \I have just sent an email