facebook login "Error validating access token"

Hi, everyone I'm using Titanium 2.1.1, windows7, android 4.1. I'm trying the facebook_login_logout.js from kitchen sink and I only change the appId and the permissions. The client has already authorized the app and when i try to login sometimes it works sometimes it doesn't and displays this error:

[ERROR][FacebookModule( 1241)] (Thread-116) [15100,116076] Error validating access token: The session has been invalidated because the user has changed the password.
[ERROR][FacebookModule( 1241)] com.facebook.android.FacebookError: Error validating access token: The session has been invalidated because the user has changed the password.
[ERROR][FacebookModule( 1241)]  at com.facebook.android.Util.parseJson(Util.java:285)
[ERROR][FacebookModule( 1241)]  at ti.modules.titanium.facebook.FacebookModule$3.onComplete(FacebookModule.java:331)
[ERROR][FacebookModule( 1241)]  at com.facebook.android.AsyncFacebookRunner$2.run(AsyncFacebookRunner.java:254)

That's my code :

var win = Ti.UI.currentWindow;
Titanium.Facebook.appid = "41793xxxx815156";
Titanium.Facebook.permissions = ['read_stream','user_birthday','user_location'];
// Login Status
//
var label = Ti.UI.createLabel({
    text:'Logged In = ' + Titanium.Facebook.loggedIn,
    font:{fontSize:14},
    height:'auto',
    top:10,
    textAlign:'center'
});
win.add(label);
 
var forceButton = Ti.UI.createButton({
    title:'Force dialog: '+Titanium.Facebook.forceDialogAuth,
    top:50,
    width:160,
    height:40
});
forceButton.addEventListener('click', function() {
    Titanium.Facebook.forceDialogAuth = !Titanium.Facebook.forceDialogAuth;
    forceButton.title = "Force dialog: "+Titanium.Facebook.forceDialogAuth;
});
win.add(forceButton);
 
function updateLoginStatus() {
    label.text = 'Logged In = ' + Titanium.Facebook.loggedIn;
}
 
// capture
Titanium.Facebook.addEventListener('login', updateLoginStatus);
Titanium.Facebook.addEventListener('logout', updateLoginStatus);
 
//
// Login Button
//
 
    win.add(Ti.Facebook.createLoginButton({
        top : 300,
        style : Ti.Facebook.BUTTON_STYLE_WIDE
    }));

Thanks for your attention.

first your user must logout from the system, since the problem is this

validating access token: The session has been invalidated because the user has changed the password.

your user has change his password and this will make the access token invalid.