Lost 20 000 rands as Prestige client of Standard Banks and no proper feedback from bank one week later.

I have banked with Standard bank as a prestige account holder banker for over a decade. On August 31 , I lost close to 20 000 rands due to *****ulent activities on my account. I say on my account because I did not loose my card, and therefore my card was not compromised. I still have my card up to now. I did not authorize any of these transactions yet money was repeated taken out of my account with no request for an OTP. As far as I am concerned every online transaction needs to be authorized via an OTP or the banking app. I believe that Standard banks systems are not secure and are vulnerable. Standard has not given me any proper feedback or refund 1 week later. I am very disappointed in this bank and advise any one willing to listen to move to another bank. Standard bank please resolve my issue as soon as possible. I never authorized any of those transactions. I need my money back.