Incorrect Balance information

I received a statement for my account in May upon request. On 19 September 2017 I requested a balance and was informed that I will have it in 3-5 working days. By 19 October 2017 and after numerous calls and emails I still did not receive a balance. All I was told was that I have to email the necessary departments requesting the amount, which was done on numerous occasions. I was informed this morning that the amount I owed was R10000 more than what I had in May, while paying R2500 on average every month.