SSDA AND FNB - worst service

Pathetic service!!! This company is the worst of them all. In November I get a call about them offering me a settlement discount on my loan account. I accept, we set up the debit order to go off, I specify the account number with the SSDA agent on the phone. THEN the agent picks the wrong account - after I confirmed the last digits of the account to be debited. So the debit order bounces because she picked the wrong account. THEN I GET PENALISED FOR THE SSDA AGENT'S MISTAKE and the settlement discount is written back to my account. After numerous letters and them just taking money form my account, I get another "offer" to settle my account - a promised 80% discount per sms…..when I phone them they say no the sms is wrong, they can offer me a 20% discount...… I accept the 20% discount, they send me a settlement letter, and whilst I am busy loading the details to pay the amount per the settlement letter, they take the full amount from my account (not the discounted amount). What's worse? A week later another R500 debit order off my account for an account that has been paid in full!!!! Now I have been phoning every third day, been sending emails, same excuses - you will be refunded tomorrow....but for 4 weeks now tomorrow never comes!!! Is there a higher source where I can lay a formal complaint against FNB and SSDA, as these people keep taking our money and just get away with it!!!