This can be a caching issue (where a previous session to readings has timed out but is cached).
One way to be certain is to go to LearnJCU via a 'New Private Window' Ctrl-Shift-P and access your readings again.If it works then the problem is related to caching, but sometimes clearing cache and cookies does not resolve it.
In these cases we've had success going to:
about:preferences#privacy (literally copy and paste this into the Firefox address bar)
Scroll down to the History section
Click 'Clear history' (which is separate from cache and cookies).
If this does not work please let us know. The workaround is to use Chrome.
We acknowledge the Australian Aboriginal and Torres Strait Islander peoples as the first inhabitants of the nation and acknowledge Traditional Owners of the lands where our staff and students, live, learn and work.