Poor communication and service

On the 5th of September 2019, my companion and I missed a flight from Lanseria Airport to Port Elizabeth, booking reference SRDTHV and SRDTHW. We then made another booking to travel on the 6th of September returning on the 7th of September 2019. Upon booking, due to panic, we booked another return flight, reference number SEDZZF. This was the same flight that we had initially booked, making it a double booking for one flight. I explained at the Mango Airline information desk about my situation, I was told to call the airline's offices for a refund. My wife called in about the matter and she was told to write this email and request the refund.