Pre payment not refunded after 5 months

I signed up with Telkom mobile in March 2019. When I signed uo a prepayment of R 279.00 was taken and I was told will be refunded to me. To date I have not received my refund. After numerous calls a case was opened case: ***3. Lo and behold a few days later I received a mail case resolved. After waiting a month and no refund forthcoming numerous calls to Telkom again, the person had closed the case without doing anything?? Does this person still need to be working for your organization? Please ensure that I receive my refund as soon as possible.