Topic: Problem with "\front\helpdesk.php" - no anonym tickets

After upgrading to version 9.1.2, i decided to check the work of anonymous tickets and found that submit does not work. When i try to send a ticket using the form "front/helpdesk.php", the browser redirects me to the main page "/index.php?redirect=%2Ffront%2Ftracking.injector.php&error=3" with the error: "Session ID problem. Perhaps you have idled too long?" (on russian "Неверный пользователь для ID сеанса").
On the site demo.glpi-project.org the problem looks exactly the same. As well as on other open sites with version 9.1 and higher;).
Allow anonymous ticket creation (helpdesk.receiver) is ON.
Where to look for solutions of this problem?

Thanks in advance!