I definitely click this option and still have to sign in every day, sometimes multiple times per day, same device same browser. Very frustrating. Thank you
Do you have your browser set to automatically delete cookies when closing? If so then that might be the source of the problem. Another issue could be if the computer is shared with multiple browser accounts - but shouldn't be if the cookies are still there. Other possible issues might be any browser security or Internet connection configuration that might affect your cookies.
Community will need to know your browser version in order to possibly guide you further - it's usually in the Help> About menu.
This is probably one of the two issues that have been combined by moderators into Paul's thread (https://community.familysearch.org/en/discussion/comment/482098).