Bad Customer Service

I have a Wesbank Cash power Personal loan. During August 2020 a double premium went off. During October 2020 I spoke to a lady from customer care - she told me that she will request the refund for me. Until now no refund, no telephone call no email. Today I called again - a guy helped me and when he told me that I must hold on he will try to find out from the account department what is going on, I asked him if he can phone me back as I am on my cellphone and it is more than 10min already. He confirmed that he cannot call back. It is now more that 6 months struggling to sort out the credit. I will really appreciate it if somebody can look into the matter and give me a call explaining when I can receive the credit.