Why doesn't this display above the players character? It is the chat service.

function Talk(msg)
game:GetService("Chat"):Chat(game.players.LocalPlayer.Character.Head, msg, Enum.ChatColor.Blue)
end
Talk("Hello")

Ever since an update, this part of my script broke and now it doesn't do anything anymore. Why is that?

First of all, you have lower case game.players while it should be game.Players.

If you have the filtering enabled, that might be another reason why this doesn't work. Well it should work only for the local player, but won't be visible to others.

Other than that, there isn't really anything wrong with this code.