Kulula won't pay my refund

I had the most horrible experience with Kulula. My mom asked me to do a flight exchange for her, the exchange was completed successfully and even got a confirmation and all the money debited from my account. When my mom called in to confirm her flights, Kulula couldn't pick up the exchange. We sent them all the evidence that the exchange went through successfully on our side but the haven't assisted me with my refund since 20th of October 2021. They even asked me to go the bank to get authorisation code, which I did but still no assistance. As soon as I sent them the authorisation code, the transaction disappeared from my bank statement and they never respond to me. Every-time, I get allocated a new person to help but as soon as they have understood the stood, they ghost me. I have tried all everything to reach out, all I need is my money and nothing else. This company is a *****, I'm so disappointed.