We try to monitor the people signing in as much as possible and numerous times, we have found people signing in with fake names and emails. As soon as we find such occurences, we delete the accounts immediately. Hence, you will not find the names even though you have got notification of new signees. Also sometimes, people who sign up, realise that they have signed up for the wrong year and request to be changed to another year. So when these people accounts are transposed, you will not see them either in your class roll.