But I doubt there is any casino that would log you out due to inactivity.
I have a sporty bet account that logs me out of the account whenever I fail to log in perhaps within a duration 4 -7days and it makes me know that with frequent login and participating gambling activities, the site remains open based on the activities of the user/gambler.
Couldn't KYC verification also be an issue that makes a gambling site to always log out users ones they have left the site dormant or inactive for a while, no matter how short or long the duration is?
If I have that experienced, I will not use that site and will search for the other site. You can report it to support services so they can follow your problem and hopefully, that will not happen in the future especially to other members.
If members left the site dormant or inactive, the site require them to activate their account by asking for a help from support services. But maybe they can enter to their account without do that so that will depends on each casino. But maybe some casino can log you out from their site due to inactivity and for security reason.