Refund from Unisa since I couldn't study nor deregister

I registered first semester for a short course , I couldn't log into my myunisa where I get my assignments and communication between the school and I , once Covid-19 hit with lockdown I couldn't get assistance and I still can't. The first semester is almost over and I can't talk to them about getting a refund I paid I couldn't even deregister as I need to be logged onto Myunisa to be able to deregister