Unisa financial department sucks

I had a credit of R2000.00 plus with Unisa last year that was not transferred over to this year for my studies, I have sent two mails regarding the situation to Unisa with no response, I even added screen shots of the previous statement and this years statement to show them, I have not received any response, I have also been calling them more than sixty times but the financial lines stay busy as per their web address.

I have to pay my studies before the end of March 2018 but I want the R2000.00 to reflect before I make a payment, I feel Unisa says that you must pay, pay, pay but your funds go missing in the process