Breach of agreement and false promises

Absa bank contacted me and offered me a 20% discount on my loan account if i agree to pay it off within 3 months which i agreed upon over the phone. My last payment is due now and absa has failed to stick to the agreement. My statements received 2 weeks ago shows i need to still pay the full amount. My father whom has rights to my account has been to the bank manager in herm**** and they have sat together listening to the phone call agreement that was recorded and the bank manager has told my father not to pay absa anything until the letter of agreement was sent to him which was 2 weeks ago and they promised him he would have it the next day. I still have not received this letter and when i contact the absa herm**** branch from outside the country and i ask to speak to the bank manager as it is urgent as my account needs to be paid the lady tells me there is nobody that can assist me there not even my personal banker Johann Viljoen or the gentleman at customer care in absa Michael Haas. I was told i would be contacted back but received no phone call. I then contacted absa legal department that when talking to the person cuts me off and just transfers me to the action line.