UNAUTHORISED DEBIT FNB DOESNT REFUND

There was an unauthorised debit that went off my credit card, after numerous calls and chats nobody assisted or gave me conflicting info, one says I need to pay R120 for another card and cancel the current one and i may not be refunded. Today i called the call center and was put on hold for almost 30minutes and still nobody assisted. The dispute was logged on the app and there is no record of that in fnb system. I cannot believe how disgusting the customer service is. One person says i can get proof of payment only on a weekday another says there is no proof of payment on credit card transactions. How did fnb allow the amount to go off without my authorisation or even a debit order? I asked for a supervisor to contact me and nobody did. Its been three weeks and FNB has not refunded me or even provided me with a way forward, I will definetely be changing banks.