PHP Session始终处于活动状态

When I start a session with session_start, the session is starting.

if (session_status() == PHP_SESSION_ACTIVE) {
echo'cc';
}

returns 'cc';

But when I want to disable the session, it empties $_SESSION but when I check if the session is still active:

if (session_status() == PHP_SESSION_ACTIVE) {
echo'cc';
}

it still returns 'cc'...

To disable the session, I tried session_destroy, session_unset, unset($_SESSION)..