Problem in UPDATE with CRUD made with JQuery and Bootstrap

When I update one of the rows is perfect, the problem appears when I want to update another row. In addition to updating the selected row, the row that I updated earlier is updated, with the same data.

I leave you a capture of what happens: link

    $(document).on("click", ".updateRow", function() {
var idUpdate = $(this).parent().parent().attr("id");
$(".titleUpdateModal").val( $(this).parent().parent().find(".titleRow").text() );
$(".descriptionUpdateModal").val( $(this).parent().parent().find(".desciptionRow").text() );
console.log(idUpdate);
$(document).on("click", ".btnUpdateModal", function() {
    var JSON = {};
    JSON.id = idUpdate;
    JSON.title = $(".titleUpdateModal").val();
    JSON.description = $(".descriptionUpdateModal").val();
    $.post("api/update.php", JSON, function(data) {
        getData();//imprime de nuevo los datos en pantalla
    });
});

});

<div class="modal fade" id="updateModal">
  <div class="modal-dialog">
    <div class="modal-content">
      <div class="modal-header">
        <h5 class="modal-title">Update</h5>
        <button type="button" class="close" data-dismiss="modal">
          <span>&times;</span>
        </button>
      </div>
      <div class="modal-body">
        <input class="form-control mb-2 titleUpdateModal" type="text" placeholder="Title">
        <input class="form-control descriptionUpdateModal" type="text" placeholder="Description">
      </div>
      <div class="modal-footer">
        <button type="button" class="btn btn-secondary" data-dismiss="modal">Close</button>
        <button type="button" class="btn btn-primary btnUpdateModal">Update</button>
      </div>
    </div>
  </div>
</div>

Connection details

<?php

require 'Database.php';

$id = $_POST["id"];
$title = $_POST["title"];
$description = $_POST["description"];

$connection = new Database();
$sql = "UPDATE items SET title = ?, description = ? WHERE id = ?";
$query = $connection->prepare($sql);
$query->bindParam(1, $title);
$query->bindParam(2, $description);
$query->bindParam(3, $id);
$query->execute();

?>