Utterly disappointed with UNISA #ABT1520# Worst learning experience!

I'm highly dissapointed in how UNISA engages and assists students. I registered for a module and followed all the correct protocols. On the day of exam, the submission link was not working and the lecturer provided an alternative CEDU link and I submitted through that link. I submitted and there was no confirmation to validate submisssion as per respective norm and I emailed the lecturer to alert them, but no the lecturer ignored and did not respond. I'm a student has been aiming for distinctions and now the lecturer says its because I did not include correct aspects in my exam and did not submit correctly. This was all done correctly as plagiarism pledge was attached and all questions were answered to the best of my ability. The lecturer just brushed me off, saying speak to exam office and is not even bothered to advise on the way forward. I have receipts all email correspondence, I truly regret this institution, what happened to customer service?