Weird error?

ID = os.getComputerID()
os.setComputerLabel("CnS_Turtle_"..ID)
verify = fs.list("")
disk_commandList = fs.list("disk/CnS")
--verify that there is or is not a CnS directory
for i = 1, #verify do
	if verify[i] == "CnS" then
		term.clear()
		term.setCursorPos(1,1)
		print(" ...CnS Turtle Successfully booted...")
		print("Turtle ID is "..ID..".")
		print("Please issue a command in order to begin.")
		print("Type \"prog\" to see the list of loaded applications and type \"auto\" to setup automation.")
		break
	else
		--install CnS package
		for i = 1, #disk_commandList do
			fs.copy("disk/CnS/"..disk_commandList[i], "CnS/"..disk_commandList[i])		
		end
		os.reboot()	  
	end
end
  
commandList = fs.list("CnS")		  
function commandPrompt()
	command = io.read()
	for i = 1, #commandList, 1 do
		if command..".lua" == commandList[i] then
		  
			if command == "terminal" then
				return os.run({}, "CnS/terminal.lua")
	  
			elseif command == "auto" then
				return os.run({}, "CnS/auto.lua")
		  
			else
				print("*You issued the "..command.." command.*")
				os.run({}, "CnS/"..command..".lua")
				return commandPrompt()
			end
		end
	end
	print("Not a valid command.")
	sleep(.5)
	return commandPrompt()
end
commandPrompt()