How do you check if something in workspace isn't there?

Hi, thank you for reading. What I'm trying to do here is that after every 2 seconds, if there is no object in workspaced named "Foil", then the script will fire and a "Foil" from Lighting will clone into the workspace. The problem is that it keeps spawning the foil after I removed it when I clicked it. It just spawns infinitely and it bothers me that it does that. Can anyone help me?

Material = game.Lighting.Loot:getChildren()
Foil = game.workspace:WaitForChild("Foil")

	while wait() do
 print("Spawning")
  wait(2)
  for i = 1, #Material do
 if Material[i] and Material[i]:findFirstChild("Foil")  then
	if Foil.Parent ~= game.workspace then
	Materials = Material[i]["Foil"].Parent:Clone()
    Materials.Parent = workspace
	Part = game.Workspace.Part
	if Part ~= nil then
	Materials:MoveTo(Part.Position)
				end
    		      end
  	   end
	end
end

This is just an exemple:

Childs = { } -- Table

function Find()
	for i, a in pairs(workspace:GetChildren()) do
		table.insert(Childs, a)
	end
	for i, b in pairs(Childs) do
		if tostring(b) == "lewl" then -- If in the workspace you found an Instance named "lewl" then
			print("here") -- Say here
			Childs = { } -- Cleaning the Table
		else 
			print("Not here")
			Childs = { } -- Cleaning the Table
		end
	end
end

while true do
	wait(2)
	Find()
end

This has been asked before. (Right)