Username does not work with email

More often usernames are the email address so djames is a unix user and has email address but because companies have not typically held onto the unix name schema and people have tried to avoid spam and so on it has become a mess (Leave your comments below) with goverment bodies such as LEA’s not being able to correctly address users, even to the point of naming the server host for example username@blueserver.domain.edu there seems to be no RFC. if you know of one please leave your comments below