The context has expired and
can no longer be used
This message is displayed to everyone, Doing an iisreset would get the site working but that will last for a day at the most.
Solutions: The issue could be of many reasons here in the Article I am providing the solutions for the most common.
Solution 1: Do Recycle AppPool\IISreset to resolve the issue temporarily.
Solution 2: Ensure that the below settings are configured correctly.
1.
Select
Time zone is configured properly on web application General settings.
2. Ensure that
the Date and Time options on your server and time zone is configured
correctly.
Solution 3: Disable/
Increase the “Web page Security validation” in general settings for SharePoint
web application.
Central Administration -> Application Management -> Manage Web
Application -> Select Web application -> on the ribbon select “General
settings” -> Off the Security validation/Increase security validation expire
time.
I hope the above information will help you to resolve the issue, in case of any queries/questions regarding the above mentioned information then please let me know. I would be more than happy to help you as well as resolves your issues, Thank you.