Best/Worst bank at ignoring their clients requests

By far the worst bank within South Africa, I have had a Discovery Credit card for quite a number of years without any issues, however they just decided to give me 2 extra cheque accounts for no apparent reason, and when i asked them to close these accounts down i was told i would need to settle the outstanding bank fees before they would be able to close the account down. I have not used these accounts nore do i plan on using them, Finally after months of fighting i managed to have one of the accounts closed, but now still have one active with over R 1 000.00 in bank fees which i refuse to pay as i did not ask for these cheque accounts. Is there anyone who would be able to assist me with closing this ****** account down.