Cheque Account fees frustration

I opened cheque account with FNB my salary started going in this account on the 15/01/2019. I was told my fees would be R105. To my surprise my account is on -R695 I can't even move my last money from my savings pocket because of this minus. On the 17/06/19 it was -R454, 18/06/19 R133 available balance, 19/06/19 -R570 & 20/06/19 -R675 to date. Why would I owe FNB R675 if cheque account fee is R105. On Thursday I got an SMS to say it has all been fixed they had technical errors but til now I still owe FNB R675 for what.

I am moving my salary to another bank together with the funeral policy I have with FNB I'm cancelling. Its not even a year I started banking with them & already I owe them R675 which I don't even know why. Their fees have moved from R105 to R675. Its too much & expensive, when u go to their branch there is no explanation.