I am not getting any respond from unisa.

i have sent the following email to unisa countless times!!!! I am still waiting for a response!!! <br> i am very disappointed in UNISA!!! I have been emailing you guys about a problem for a long time now. Please assist me!!!! I paid all my fees last year! Then in December i suddenly saw that you guys are requesting another R690 and the statement says REINSTaTE PST104F. Where do you guys get this amount from ??? I paid all my fees in full!!!! I paid my deposit for the first semester 2015 which was R3440. It is alot of money. Now you guys deducted the R690 from that. And now i still cant start with my studies as there is R690 ' missing'. Please fix this mistake!!!! I do not owe that R690. And i need you to reinstate me so that i can start with my studies. I dont have that R690 to pay again. Please reapond to this!!!!! <br> *** and my student number ***3