Getting error DataTables warning: table id=example- Cannot reinitialise DataTable.

i have this error when i search by id

 function ToDatatable() {

        var Arr = [];
        var searches = "";$.ajax({
            type: "GET",
            url: "/Healthcare_Physician/getColumns",
            data: {
                id: $("#id").val(),
                first_name: $("#first_name").val(),
                designation: $("#designation").val(),
                department: $("#department").val(),


                type: "GET",

            },
            success: function (response) {
                searches += "<tr>";
                data = $.map(response, function (item, a) {
                    Arr.push({ data: item.variable, title: item.variable });
                    //   searches += "<td><input style='width:100%' type='text' id=" + item.variable + " class='form-control' placeholder='Search " + item.variable + "'/></td>";
                });
                //  searches += "</tr>";
            },
            dataType: "json"
        }).done(function () {$('#example').append(searches);
            var sample = $('#example').DataTable({"language": {"zeroRecords": "Nothing found - sorry","emptyTable": "No data Available.","loadingRecords": "Loading...","processing": "Processing...","lengthMenu": "Display _MENU_ records per page",
                    // "info": "Showing page _PAGE_ of _PAGES_","infoFiltered": "(filtered from _MAX_ total records)",
                    // "sDom": 'Rfrtlip',
                    // stateSave: true,
                    //"bDestroy": true,"retrieve": true
                },"dom": '<"top"f>rt<"bottom"ilp><"clear">',"ajax": {"processing": true,"serverSide": true,"url": "/Healthcare_Physician/ConvertDataTabletoString","data": {"id": $("#id").val(),"first_name": $("#first_name").val(),"designation": $("#designation").val(),"department": $("#department").val(),


                        type: "GET",

                    },
                    "dataSrc": "","deferRender": true,


                },
                "columns": Arr,"sortable": true,"bFilter": true,"scrollX": true,"searching": false,"bInfo": false,"lengthMenu": [[10, 25, 50, -1], [10, 25, 50, "All"]],"columnDefs": [
                    @* {"render": function (data, type, row) {

                    switch (data) {
                        case 'Submitted': return '<img src="@Url.Content("~/img/blue.png")" style="width:8px;height:8px">&nbsp;&nbsp' + data + ''; break;
                        case 'Draft': return '<img src="@Url.Content("~/img/red.png")" style="width:8px;height:8px">&nbsp;&nbsp' + data + ''; break;
                        case 'Cancelled': return '<img src="@Url.Content("~/img/red.png")" style="width:8px;height:8px">&nbsp;&nbsp' + data + ''; break;

                        default: return '';
                    }
                },
                "targets": 1,
            },*@
            { "visible": false, "targets": [5, 6] },

            {
                "render": function (data, type, row) {

                    return '' + data + '';
                },"targets": 1,
                     },

                ]
        });

        var row;
        for (var i = 0; i < Arr.length; i++) {

            row += "<option>" + Arr[i].title + "</option>";
        }$("#list1").empty();$("#list1").append(row);
    });

    //$("#example").off("click", "tr").on("click", "tr", function () {

    //    var series = $(this).find("td:eq(1)").text();
    //    window.open("edit_Terms_and_Conditions_Template?series=" + series + "", "_self");

    //});


    var rowlist = [];
    $("#example").off("click", "tr").on("click", "tbody tr", function () {
        // alert($(this).index());
        var series = $(this).find("td:eq(0)").text();

        window.open("edit_physician?series=" + series + "", "_self");

    });

    }



  $("#id").on("keydown", function () {
        setTimeout(function () {

            if ($.fn.dataTable.isDataTable('#example')) {$('#example').DataTable().destroy();$('#example').empty();
            ToDatatable();

        }
        else {
            ToDatatable();

        }

            }, 1000);
    });