are you talking about a user within the same account or a completely separate account? What player model? I will assume it is all within one account. I have a samsung player and when accessing netflix, though I am auto logged in, it will go to a screen that has my account, kids account and add new user (not exact wording). so it seems if a new user is added, their profile would appear on that screen.
One thing you can try to do. reset your player to factory default and setup your account. also make sure the player has the latest updates.