Jquery AJAX not working with session It is not taking old session.

In my rails application when I trigger a Ajax request with my
javascript in below way

$j.ajax({
  type: "POST",
  url: "https://fbapp.pinkienow.com/requests",
  data: "requstids="+response.request_ids
}).done(function( msg ) {
  alert( "Data Saved: " + msg );
});

The request is firing correctly but it is not taking my old session
values of user

It is showing error that your session variable is not available in my
log

any idea why it is not taking previous session ?
and how to fix that ?

Thank you in advance.

I got solution

we need to add below code in your header javascript, which tells use
browser cookie in server externally