Given wrong Settlement amount

ive been banking with standard bank for more than 10 years and i had 2 loans that i took out with them, more than 5 months ago i went to the branch in Randburg square to ask for settlement letters for both loans and i was given two settlement amount, a few min later i went to my new bank capitec and i settle both the loans with standard bank. Yesterday on the 25th of Nonmember i received a call from a consultant from standard bank tarynn she told me that my loans are still owing more than R1000 each i told her i paid both the loans a few months ago she then spoke to her supervisor and told me the mistake was on their side the person who gave me the settlement amount made a mistake she also said they will fix it and send an email to their Admin department to cancel the amount for me i just need to go to the branch next week Wednesday to cancel the loan off there database. Today i get called back and the guy who was assisting me told me 'IM SORRY\ the is nothing they gonna do about it i just need to pay the amount. i don't see why i have to pay this amount where as i paid all the money they said i should pay i have never in my life received this kind of bad service im so angry"