plr.Chatted event not working?

game.Players.PlayerAdded:connect(function(plr)
	print("Player Added!")
	plr.Chatted:connect(function(msg)
	print("Player Chatted!")
		if msg == "hi" then
			print("Hello, "..plr.Name.."!")
		end
	end)
end)

I have put this into a regular script in ServerScriptService, but nothing happens, I thought it was because of FilteringEnabled since I am working on a project that requires FE. But turning it off does nothing. I have tried putting the code into another place, nothing happens. I added the print() function on both events, but it appears that the Chatted function is not firing, Is anybody able to help me with my situation?

(By the way, this was just test code, not part of an actual project.)