Pure incompetence

Following my previous complaint, Standard Bank has again shown their incompetence by billing me incorrectly on the home loan I had complained about. On Saturday 31 October I got a calling saying that I'm in arrears by R300 on my account. I pay an extra R500 on this bond by debit order, how am I arrears!!?? Even the agent that called couldn't answer me. Applying for this home loan has been nothing but a nightmare and the bank seems determined to ruin my credit record by the time I'm done. Im checking my IT record in 2 months, if this default appears, im handing this over to my attorneys. If nothing is done within 2 days, im closing all of my standard bank accounts