Furious customer

I am so upset! I paid the balance of my personal loan, I had a secure chat with Smangalele or something around that name, I asked her if my loan is completely paid off she said yes, I asked her if anything is owed by me and she said no nothing is owed by me and I am done with the loan. A few days later the debit order came off my account which was R1000, I called in to the loans department and spoke to Penelope, she advised me that the money will be reversed, I asked her if R1000 will be reversed, she said yes. I waited a few days and saw the money didn't reflect and once again she reassured me that the R1000 will be reversed. A day or two later only R682 was reversed, I called in again and this time I spoke to Olga, Olga tells me a new story of how this is the interest that was deducted. Excuse me? You telling me two people gave me the incorrect story and now I will not get my money back? The service is absolutely terrible and I will never take out a loan with FNB again.