UNISA not refunding my credit

Am so very much disappointed with the administration of UNISA more especially at Port Elizabeth branch. I requested to my money(credit) back from them since 2020 February. I haven't received any feedback from them till today. I kept on going there but nothing they always say I must wait. My R1500 is the on my statement and it states clearly that it's due to me. What is that is so difficult for them to give my money back. Please assist.