Mango’s service is terrible

I booked a ticket for my granddaughter to fly with me from Durban to Johannesburg and within 5 minutes I found out from my daughter that my granddaughter will not be able to fly as she had received a scholarship to attend a doc or academy. After waiting ages on the phone I explained to the lady that I need to cancel the ticket urgently as my granddaughter cannot go with me. She advised that no refunds are allowed but I can get a travel voucher for another flight. I advised her that my daughter will fly out week after next but I do nothave the exact dates and times as yet. I asked her if I could make the booking once I had the information. She rep**** yes. When I received the dates from my daughter I tried to make the booking but could not as I was told that they needed to listen to the recorded telephone message to confirm. Eventually two weeks later I was told that I do not qualify fir a refund. I asked to listen to the recorded conversation but held on for too long.