LED On & OFF Problem

[Emaly]

Hi All.
my code doesn't work i don't know why what is the problem can some one help me please many thanks for your help. using ESP12E with Lua.

wifi.setmode(wifi.STATION)
wifi.sta.config("SSID","PASS")

print(wifi.sta.getip())
gpio.mode(2, gpio.OUTPUT)

srv = net.createServer(net.TCP, 1)
srv:listen(80,function(conn)
conn:on("receive", function(conn,request)

    local buf = "";
    local _, _, method, path, vars = string.find(request, "([A-Z]+) (.+)?(.+) HTTP");
    if(method == nil)then
        _, _, method, path = string.find(request, "([A-Z]+) (.+) HTTP");
    end
    
    local _GET = {}
    if (vars ~= nil)then
        for k, v in string.gmatch(vars, "(%w+)=(%w+)&*") do
            _GET[k] = v
        end
    end

    --print (_GET)
    
    buf = buf.."<h1> Web Server 87</h1>";
    buf = buf.."<p>LIGHT  <a href=\"?pin=ON\"><button>ON</button></a>&nbsp;<a href=\"?pin=OFF\"><button>OFF</button></a></p>";

    local _on,_off = "",""
    
    
    conn:send(buf);
    print(_GET.pin)
    print('Pin 2 is:' .. gpio.read(2))
    action(_GET.pin)

   
end)
conn:on("sent",function(conn) conn:close() end)

end)
function action(param)

    gpio.write(2, gpio.HIGH);
elseif(param == "OFF" ) then
  
    gpio.write(2, gpio.LOW);
end

end