French Teacher

Many of my students have accounts, are in my class, are using the correct username and password, but they can't get past the login page. They click on the pinkish rectangle and nothing happens. I can see their workbooks and done worksheets. 

I was paying you but no longer have a paid account. Is this why? 

My IT people are working on it but they need to know more from you. Please advise. What should I do next, what can you do and what do you suggest IT do? Thanks.