Check you SPAM settings. For the few who did not find their confirmation email, it was one of two things, both of which had to do with their SPAM settings.
1. It was in their SPAM folder.
2. They had their SPAM settings such that all emails considered SPAM got deleted and thus they could not even find it in their SPAM folder.
Hope one of those solve the problem.
Feel free to use whatever name you feel most comfortable with.