It means the cPanel monitor is broken. The database server is working fine. The problem is actually that localhost no longer points to 127.0.0.1 like it should. Change your script's database server to 127.0.0.1 instead of localhost and see if it works. If it does not, check in PHPMyAdmin and verify that the database exists and has content like it should. If it's empty or missing, let me know its name so I can escalate this for you.