So I believe Roblox Engine has a bug right now. This feature worked for me a very long time but since yesterday the messages appear above the normal player chat. So you cant see it if you wrote some messages.
If you want to reproduce the bug here:
while wait( 5 ) do
game.StarterGui:SetCore( "ChatMakeSystemMessage", { Text = "Test text", Color = Color3.new( 1,1,1 ), Font = Enum.Font.Arial, FontSize = Enum.FontSize.Size24 } )
end
If you got any Idea how to fix or smth. tell me.

1 comment
It does not. It is already. Its probably a bug in roblox, because in Studio it is working great but when you join an actuall real server it isnt.