It's beceause of Cookie Policy, to fix it, you should add this :

public void onCreate(Bundle savedInstanceState)
{
    super.onCreate(savedInstanceState);
    super.init();

    // Allow third party cookies for Android Lollipop
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
        WebView webView = (WebView)super.appView;
        CookieManager cookieManager = CookieManager.getInstance();
        cookieManager.setAcceptThirdPartyCookies(webView,true);
    }

    super.loadUrl(Config.getStartUrl());
}

if you are using Android Lollipop, then

CookieManager.getInstance().setAcceptCookie(true);

won't work. You need to use

CookieManager.getInstance().setAcceptThirdPartyCookies(true);