Corporate unable to manage limit on card

I have been banking with Standard Bank since the late 1980's and have had my corporate account with them since 2003. I was surprised to receive a call from the bank informing me that I have exceeded my limit on my business card and that I cannot use the card until the debit order goes through on the 05/11/2015 although my accounts are in good standing and has been for years. I asked why my card limit was exceeded as the bank should have managed it. The credit department unashamedly acknowledge that they cannot manage the limits very well, none the less they want to charge me for exceeding the limit. I was told that I can close my account by sending an email to [Email Removed] its time for change to a bank with respect for their clients.