Calling to collect on an account that's settled

In May 2015 I went to the Sammy Marks branch to settle an account I had opened in 2013. On this account to my knowledge I had R278, 97 to pay and close the account. When I got to one of the cashiers I was told that I have R750 and odd cents to settle the account. Spoke to the store creditors clerk Sunnel and manager Rodzani about this matter. They further called the regional manager who concluded that an amount of R250 should be paid by the account holder (me) to settle the *** ago I get calls from the debt collecting team at their head office saying I have an amount of R587 that I need to pay to settle my account. I get about 3 to 4 calls a day from these people and I explain that the account was settled. Today I went to the sammymarks branch to find out what is happening and the answer I get is that they informed headoffice about this and don't know why they keep calling me. I am sick and tired of the JD group trying to get more money out of me, and the endless calls they make to me about this account. They always bully their customers but They will not bully me to pay money on an already settled account. My experience with JDG has been nothing less than a nightmare.