The reason is a bit complicated and more than most students probably want to know, but I'm happy to explain. Kanopy is not a subscription database. Rather, as Los Rios users watch Kanopy films, our libraries automatically purchase individual licenses to the films. This means we need to budget how much the libraries should spend on the films, and it so happens that we've now reached our yearly spending limit. So at this point, you can continue to browse films in Kanopy, but you can only watch those that have been purchased.
Ideally our users would not be using this resource just for personal interest, though we also realize that's not something we can really control. But I will recommend that you also explore options available for streaming video from public libraries. Unfortunately Sacramento Public Library doesn't have much in the way of streaming video, but if you happen to visit public libraries in e.g. San Francisco or Berkeley, you can obtain a library card that will provide access to Kanopy, usually a limited number of films per month.