Refund still not returned after 6 months!

We bought a return flight ticket for my mother from Port Elizabeth to O.R. Tambo at the end of March, however to this day we have not received the refund as promised by your refund officer, Andile Dunga, despite numerous e-mails without any reply. I have also contacted your call centre, but there is no answer. Please can you get back to us with a timeline on how long the refund is going to take or issue us with a voucher instead. You are sitting with R1600 of our money with no service rendered!