Apparently no fraud detection system

I found a fraudulent charge on my checking account of several hundred dollars. I informed bank it was a fraudulent utility payment and they credited it back. Despite this warning, a few days later the bank debited another large fraudulent utility payment from my account. Again, I was the one who found it, not the bank. It appears the bank does not use Shazam or any other fraud detection service, nor does it look for fraud using its own employees.