Date for assignments closed before due date

I am highly disappointed! This is the second time I have assignment submissions have been closed before due dates due to system updates. We plan our assignments according to those dates because we have to budget for textbooks. I have not been able to upload any tasks at all due to system errors and updates. Task dates only due 23 April have already been closed! This is the second semester that Unisa just takes my money and I am not able to right exams. I should have been done with studies already but this process is costing me time and money each time A total of R9500 down the toilet!! The books requires are very expensive and need to be saved up for before purchase thus planning according to set dates have been made. I send emails and receive no replies.