How two people can have the same name  ?

https://bf4db.com/player/419130462

https://bf4db.com/player/1782796127

EA/Origin manages nicknames in a rather special way. If you take your account, log out of battlelog and change your name through origin, your name will remain the same/will stay on your old nickname on battlelog until you log into battlelog once again. As soon as you change your name through origin the nickname becomes available for others to use. And this is what happened in the case of these two players. One changed his nickname and didnt log into battlelog to update it and the other one just took it as it was available through origin.