Account paid in full but can't registered because it still unblock by unisa

I have tried from the beginning of January to get hold of unisa finance department no lucky, i have sent bunch of emails, telephone calls no response no feedback my account was handed over i have paid bur it still can't excess it because it blocked"feeblocked" and i am not getting assistance through email given for enquiries not even acknowledgement on the receipt of emails.... Why? How long must i wait or i won't register because of delays caused by unisa?