CodeIgniter-Ion-Auth: problem on remember login

i have a problem with remember login, the cookie always expire when ‘sess_expiration’ is exceeded and the users need to be relogged, i need that user is always remember if i check REMEMBER LOGIN, and is loggeout when close the browser if REMEMBER LOGIN is not checked i’m using C.I. 3.1.2 and latest version of ion_auth, with older version of C.I. 2.2.4 all work great but not with latest version

this is my setting

$config['sess_driver'] = 'database'; $config['sess_cookie_name'] = 'aaw_ci_session'; $config['sess_expiration'] = 2592000; $config['sess_save_path'] = 'ci_sessions_test'; $config['sess_match_ip'] = FALSE; $config['sess_time_to_update'] = 300; $config['sess_regenerate_destroy'] = FALSE;

$config['remember_users'] = TRUE; $config['user_expire'] = 0; $config['user_extend_on_login'] = TRUE; $config['track_login_attempts'] = TRUE; $config['track_login_ip_address'] = TRUE; $config['maximum_login_attempts'] = 3; $config['lockout_time'] = 600; $config['forgot_password_expiration'] = 0;

can you help me?