...

Read http://api.jquery.com/jQuery.ajax/: The ajax method expects the data in the data key of the settings object, not in the settings object. The data may be an object, an array or a string.

Example, stolen from the same page:

$.ajax({
  method: "POST",
  url: "some.php",
  data: { name: "John", location: "Boston" } // <-- look here!
}).done(function( msg ) {
  alert( "Data Saved: " + msg );
})
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Alexander