Hi Satomi,
See this forumpost: https://forum.mendix.com/link/questions/15402
Maybe this is helpfull.
You could try to use the IdleTimer widget. I have seen this used in the past. You are able to set the timeout and the timeout microflow that would be called when the timeout is kicked off. You could then open the page that you need.
https://appstore.home.mendix.com/link/app/305/FlowFabric-BV/IdleTimer