Not reporting new account creation

You absolutely must change the "feature" that removes extra characters from a child's account name.  My son Ben has figured out that if he created a "Ben_" account, it notified me that a new account has been created, but if he creates another account called "Ben__" (2 underscores) or "Ben___" (3 underscores), your site will remove the extra two underscores and basically ignore each of those accounts on the laptop, telling me that there is already an account for this child and rendering this protective software useless.  I have no idea where he goes on the Internet or what he is looking at, because I cannot add a child that uses more than one underscore in his name.  I am extremely disappointed and would like to cancel my account and receive a refund, unless you can make this change for me. 

I also can't monitor how long he uses the computer.