How can I stop users from clicks buttons after session expired?

 I use authentication and authorization for website, and I set the session to expire in 20 minutes.
the users will be recircted to login page if they input a url or click refresh button after session expired, it works fine
but my problem is that, if a user open a page, come back after the session expired, he still can click on a button and invoke server side event.

is there anyways to stop this please?
Thanks
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