Incompetence

I had an issue with my account I went to the bank I fixed it they changed my account details for me, last week Thursday I received a notification saying I have insufficient funds I went to the bank because my sister deposited R1200 suddenly the was an amount that was debited I went to the Braamfontein branch the guy who was assisting me said he can see that the was an amount debited but he doesn't know who did it so he will find out and get back to me the guy has dreadlocks he hasn't called me up until now so I don't know what's going.