Select2 group with Infinite scroll

I am using select2 group option with infinite scroll and data are coming by Ajax calling per page 10. Here is some problem arises, suppose user 1 has 15 data and user 2 has 15 data, at first 10 data are coming from user 1 and in next page 10 (5 data for user1 and 5 data for user2). no problem for data getting but the problem is user 1 group showing double. How can I prevent double display to my select2 options group? Has there any way to make an option group again?

HTML CODE

<div class="container">
  <form id="frm">
    <h1>Solution 1</h1>
    <div class="row">
      <div class="col-4">
        <div class="form-group">
          <label for="tagInput">Get data by ajax calling</label>
          <select class="form-control" id="pictures_tag_input">
</select>
          <small class="form-text text-muted"><p class="text-info">Infinite Scroll</p></small>
        </div>
      </div>
    </div>
  </form>
</div>

JS CODE

$(document).ready(function() {
  // solution 1
  //example.com/articles?page[number]=3&page[size]=1
  http: $("#pictures_tag_input").select2({
    placeholder: "Search for options",
    ajax: {
      url: "https://jsonplaceholder.typicode.com/users/1/todos",
      dataType: "json",
      global: false,
      cache: true,
      delay: 250,
      minimumInputLength: 2,
      data: function(params) {
        // console.log(params.page || 1);
        return {
          q: params.term, // search term
          _page: params.page || 1,
          _limit: 10 // page size
        };
      },
      processResults: function(data, params) {
        params.page = params.page || 1;
        var datx = getNestedChildren(data);
        // console.log(datx);

        return {
          results: datx,
          pagination: {
            more: true
          }
        };
      } //end of process results
    } // end of ajax
  });

  function getNestedChildren(list) {
    var roots = [];
    for (i = 0; i < list.length; i += 1) {
      node = list[i];

      if (roots.length === 0) {
        var obj = {
          text: "User " + node.userId,
          children: [{ id: node.id, text: node.title }]
        };
        roots.push(obj);
      } else {
        var obj = {
          text: "User " + node.userId,
          children: [{ id: node.id, text: node.title }]
        };
        var rootArray = $.map(roots, function(val, i) {
          var vl = "User " + node.userId;
          if (val.text === vl) return val;
          else return undefined;
        });
        if (rootArray.length > 0) {
          var obj1 = {
            id: node.id,
            text: node.title
          };
          rootArray[0].children.push(obj1);
        } else {
          roots.push(obj);
        }
      }
    }
    return roots;
  }
});

Demo https://codepen.io/mdshohelrana/pen/MLVZEG

Just try to use the following code

templateResult: function(data) {
 if (typeof data.children != 'undefined') {
  $(".select2-results__group").each(function() {
   if (data.text == $(this).text()) {
    return data.text = '';
   }
  });
 }
 return data.text;
}

NOTE: Need to group from server side, Other wise you have to make master details from client side.