Refund complaint

I closed my account 12 months back with them, unfortunately I did not delete the beneficiary on my app and on the 27/03/2020 I made a payment to the closed account by mistake for the amount of R500.00. I called them on this number: *** and I have been asked to send the proof of payment and copy of my ID so that I can be refunded, send them on the 24/04/2020, 04/05/2020, 12/05/2020 and again on the 13/05/2020, they said they did not receive my e-mails, and from my site it shows that from the first one it went through. I have to keep on calling and I am receiving the same story and holding on forever. On the 12/05/2020 I spoke with Nokubonga and Nandi, they still did not assist me. Nandi asked me to take the documents to the nearest Ackerman's store and I did gave them to the manager who said she did send them and make follow up and they still saying they did not receive them. At this stage I just need to get the refund from the Ackerman's store and they taking me from pillar to pillar am very disappointed from them about the pathetic service I have received from them.