"Uncaught Unexpected literal at position 2" from MultiDatesPicker Plugin

"Uncaught Unexpected literal at position 2" from MultiDatesPicker Plugin

I am using [MultiDatesPicker](  http://multidatespickr.sourceforge.net/ )  plugin in my Rails project. My goal is to do an Ajax call and then get the dates which needs to be disabled. After that, once I will click any enabled date it should select a range of date as per the Ajax response `interval`. Here is my code :

    $(function() {
      $(document).on('change', '#booking_package_type', function() {
        var bol = $.inArray( $(this).val(), [ "weekend", "full_week", "midweek", "" ] );
        var pkg_type = $(this).val();
        //....
    
      $.get( "/admin/bookings/fetch_dates", { package_type: pkg_type } )
        .done(function( data ) {
          console.log( data.interval );
          $('#booking_start_date').multiDatesPicker('resetDates', 'disabled');
          $('#booking_start_date').multiDatesPicker({
            dateFormat: "yy-mm-dd",
            mode: 'daysRange',
            autoselectRange: [0, data.interval],
            addDisabledDates: data.dates
          });
        });
      });
    });

But once I am clicking on any enable date, I am getting the error as :

    Uncaught Unexpected literal at position 2

Any idea why am I getting the error ?