Money *****ers!

I have called standard bank twice with regards to money in my bond account that has been withheld. Operators can't give me a clear answer. This account is supposed to be closed. They got there settlement amount and I have waited out the notice period all monies left in that account should have been paid to me. Instead they withheld an amount equivalent to a monthly installment. I have paid everything I need to. Why is the account not closed and why is money being withheld! ******** they want every last drop of money a person work so hard for. I've been with this bank so long but refuse to help or negotiate in anything. For years iv been paying extra on my bond and they have refused to negotiate a better interest rate for me therefore I have switched and now they do this it's pathetic. I have even emailed them yet no response.