Hello! Authorization on the site is written using cookies.
SetCookie ('Login', mysql_real_escape_string($_POST['login']),time() + 1800);
For several months everything worked fine, and suddenly the problems started, some users started to set the lifetime of the cookies incorrectly. Those. it turned out that cookies were immediately deleted after installation. If you delete the lifetime setting, everything starts working. Do not tell me what could be the problem?