Having problem with humanoid name display distance can anyone help?

When in game you cannot see each others name and i copyed everything in game onto another game (except test service, network client (Team Create), and terrain) and usernames could then be seen so i ran a two player test server on the first game and found in the humanoid it said NameDisplayDistance 0 but i have no idea how to change this so that its 100 for all the players. I tried

 for i, plr in pairs(game.Players:GetPlayers()) do
    if plr.Character:WaitForChild("Humanoid") then
        plr.Character.Humanoid.NameDisplayDistance = 100
    end
end

But it had no effect anyone know what the issue could be?

Use DisplayDistanceType.

 for i, plr in pairs(game.Players:GetPlayers()) do
    if plr.Character:WaitForChild("Humanoid") then
        plr.Character.Humanoid.NameDistanceType =Enum.HumanoidDisplayDistanceType.None
    end
end