Can Some on help me with this clean up script?

when i say clean up it don't work. can someone help me to fix it as i need to work for my tycoon as it all ways flooding with bricks.

function onChatted(msg, recipient, speaker)

	local source = string.lower(speaker.Name)
	msg = string.lower(msg)
--------------------------------------command between these bits--------------------------------------
	if (msg == "clean up") then
	cf = game.Workspace:GetChildren()
		for i = 1, #cf do
			if cf[i].Name == "TycoonBrick" then
				cf[i]:remove()
			elseif cf[i].Name == "UpgradedTycoonBrick" then
				cf[i]:remove()
			elseif cf[i].Name == "BestTycoonBrick" then
				cf[i]:remove()
			end 
		end

	end




--------------------------------------command between these bits--------------------------------------

end



function onPlayerEntered(newPlayer)
	newPlayer.Chatted:connect(function(msg, recipient) onChatted(msg, recipient, newPlayer) end) 
end

game.Players.ChildAdded:connect(onPlayerEntered)