Costly bank charges and no help from the branch.

I have Cheque account at Nedbank, and according to my knowledge can't go into and have never gone into overdraft. Last month my balance at ATM wasn't the actual balance left in my acc. So I swiped according to balance at ATM, Nedbank charged me R90 for every transaction no matter how small. Leaving me with an amount in arrears. The Uitenhage branch was absolutely no help, even wanted to charge me R60 just to look at my acc to see what I was talking about. They say the acc takes 3 days to update on a chip card which was never explained to me. Customers should be made aware of charges!! And what about all of the people that don't check their accounts, nedbank takes their share of your salary! I don't work for bank charges! I want to close my accounts at Nedbank sick of all their high bank charges!