**** on my Standard Bank Credit Card

I was ****med on my credit card and the bank did not handle my complaint correctly. I feel bad that I lost R16 500.00 on my credit card and after reporting to the bank, they did nothing except send me messages that they are investigating the *****ulent transaction. After 10 days, they returned to me to tell me that I authorized the transaction. My question is, what were they investigating for ten days? I feel very vulnerable as a client and the bank cannot even give me information on who the merchant is ****ming me. Otherwise will get rid of my credit card soon.