Not all loaders work in Flash AS3 - actionscript-3

Question

Hi ive been working on some project that needs to have a login system. I got it linked now with the database the problem is the other Loaders doesnt work in my system please help! Thanks in advance :)
When I click Login and Register it works fine and goes to the designated link of a diff .swf file:
but after logging in, these server buttons doesnt work on the .swf they were linked
This is my code :
package
{
/*
always extend a class using movieclip instead of sprite when using flash.
*/
import flash.display.MovieClip;
import flash.events.*;
import flash.net.*;
import flash.text.*;
import flash.display.Loader;
import flash.net.URLRequest;
import flash.events.Event;
import flash.events.ProgressEvent;
public class main extends MovieClip {;
var loadit = new Loader();
public function main():void
{
/*
buttonMode gives the submit button a rollover
*/
submit_button.buttonMode = true;
register_button.buttonMode = true;
quit_button.buttonMode = true;
server1_button.buttonMode = true;
server2_button.buttonMode = true;
/*
what this says is that when our button is pressed, the checkLogin function will run
*/
submit_button.addEventListener(MouseEvent.MOUSE_DOWN, checkLogin);
quit_button.addEventListener(MouseEvent.MOUSE_DOWN, gotoLogin);
register_button.addEventListener(MouseEvent.MOUSE_DOWN, gotoRegister);
server1_button.addEventListener(MouseEvent.MOUSE_DOWN, gotoLobby);
server2_button.addEventListener(MouseEvent.MOUSE_DOWN, gotoLobby);
/*
set the initial textfield values
*/
username.text = "";
password.text = "";
}
function gotoLobby(event:MouseEvent)
{
trace("you clicked me");
loadit = new Loader();// here it is instantiated
addChild(loadit);
loadit.load(new URLRequest("lobby.swf"));
}
function gotoLogin(event:MouseEvent)
{
trace("you clicked me");
loadit = new Loader();// here it is instantiated
addChild(loadit);
loadit.load(new URLRequest("login.swf"));
}
function gotoRegister(event:MouseEvent)
{
trace("you clicked me");
loadit = new Loader();// here it is instantiated
addChild(loadit);
loadit.load(new URLRequest("register.swf"));
}
/*
function to process our login
*/
public function processLogin():void
{
/*
variables that we send to the php file
*/
var phpVars:URLVariables = new URLVariables();
/*
we create a URLRequest variable. This gets the php file path.
*/
var phpFileRequest:URLRequest = new URLRequest("http://localhost/Perdigana/controlpanel.php");
/*
this allows us to use the post function in php
*/
phpFileRequest.method = URLRequestMethod.POST;
/*
attach the php variables to the URLRequest
*/
phpFileRequest.data = phpVars;
/*
create a new loader to load and send our urlrequest
*/
var phpLoader:URLLoader = new URLLoader();
phpLoader.dataFormat = URLLoaderDataFormat.VARIABLES;
phpLoader.addEventListener(Event.COMPLETE, showResult);
/*
now lets create the variables to send to the php file
*/
phpVars.systemCall = "checkLogin";
phpVars.username = username.text;
phpVars.password = password.text;
/*
this will start the communication between flash and php
*/
phpLoader.load(phpFileRequest);
}
/*
function to show the result of the login
*/
public function showResult(event:Event):void
{
/*
this autosizes the text field
***** You will need to import flash's text classes. You can do this by adding:
import flash.text.*;
...to your list of import statements
*/
status.autoSize = TextFieldAutoSize.LEFT;
/*
this gets the output and displays it in the result text field
*/
status.text = "" + event.target.data.systemResult;
if (event.target.data.systemResult != "Incorrect username or password. Please try again!")
{
status.visible = false;
username.visible = false;
password.visible = false;
username_lbl.visible = false;
password_lbl.visible = false;
password_lbl.visible = false;
password_lbl.visible = false;
register_button.visible = false;
submit_button.visible = false;
server1_button.visible = true;
server2_button.visible = true;
server3_button.visible = true;
quit_button.visible = true;
}
}
/*
the function to checkLogin
*/
public function checkLogin(e:MouseEvent):void
{
if (username.text == "" || password.text == "")
{
/*
if username or password fields are empty set error messages
*/
if (username.text == "")
{
status.text = "Please enter your username";
status.visible = true;
}
else if (password.text == "")
{
status.text = "Please enter your password";
status.visible = true;
}
}
else
{
processLogin();
}
}
}
}
when I click the servers theyre getting the correct output as "you clicked me" but stays on that swf please help!