Why isn't my anti exploit script isnt detecting ChildAdded?

local reason
game.Players.ChildAdded:Connect(function(plr)
	local function kick()
		plr:Kick(reason)
	end
	plr:WaitForChild("PlayerGui").ChildAdded:Connect(function(child)
		if child:IsA("ScreenGui") then
			if child.Name == "BubbleChat" or child.Name == "Chat" or child.Name == "Freecam" then
				print('loaded')
			else			
			    local reason = 'Executing a ScreenGUI'
			    print(reason)
			    kick()
			end

		end
	end)
end)

So, whenever I join the game, the first thing I see in the output is "loaded" because I made it print loaded whenever a child with the name "BubbleChat", "Chat", or "Freecam" is added into PlayerGui.

But. whenever I go into Explorer (in-game) and insert a new ScreenGui into my PlayerGui, it is supposed to kick the player and print the reason, "Executing a ScreenGUI". But unfortunately, it doesn't do that.

I really do not know what the error is here. There is no error in the output. Help is greatly appreciated!

I figured it out, I made the script a LocalScript and put it into StarterPlayerScripts. I also changed the script to:

local reason
local plr = script.Parent.Parent
	local function kick()
		plr:Kick(reason)
	end
plr:WaitForChild("PlayerGui").ChildAdded:Connect(function(child)
		if child:IsA("ScreenGui") then
			if child.Name == "BubbleChat" or child.Name == "Chat" or child.Name == "Freecam" then
				print('loaded')
			else			
			    local reason = 'Executing a ScreenGUI'
			    print(reason)
			    kick()
		end
	end
end)