For some reason I never received an sms for the first two debit orders. Still, with FNB:
1.) To stop the debit order online costs R5. Bank makes money.
2.) I don't want to go in to the branch and wait to be helped when I've got work to do. Time = money.
It's b/s that I should even need to spend 2c or 5 minutes when the institution who's responsibility it is to safeguard my funds is letting other people access it. The problem is also the millions of people who aren't aware this is going on, who haven't got the means to go into the bank whenever they want or to access online banking. It's not enough to just say 'oh well we're going to let people take money from your account but you must sort things out when it happens'.
I'd have said the same thing as you a few months ago until this happened to me

. It's hella frustrating.