Worried student

I registered for Postgrad Diploma last year and wrote my final exam in April 2019. I then inquire about my results only to be told I did not register. How did I write the exam and where are my results. I send many emails and called many times to all campuses. The lady in KZN dropped the phone after I asked her questions. This is the second time that I had to struggle to get my results. They keep on telling me my results were posted on the student portal and I kept on telling them is my old results and I registered to rewrite the one subject I failed. My student number is 139657