Standerdbank very very dissapointed

I just went to standerdbank brackenfell branch to close my account and the consultant tells me I can't close it because I have a balance of - R1200 still on my savings account *** I changed to a cheque account last year the consultant said his gona close my savings account now I must pay R1200 and that is for bank charges only because there we no money in ? How can a Savings account go in a overdraft is that f..... Possible ? I don't have the money to pay it at all !!! Why didn't they contact me the 1st month to tell me I'm in a overdraft on the account and its still open ? Very dissapointed in Standerdbank to think I were with them for ?10years wount recommend anybody to bank with them very very very bad service