code event[] calendar in laravel 8 not working

I created a calendar with laravel 8, I have successfully saved data in the database but the data in mysql does not appear in the calendar, even though I have used event[], I have checked that the data from mysql can come out but the data does not appear in the calendar, I can’t find error message, I sent my code for you to check, please help me, thx

K_JadwalController

public function index()
    {
        $data = K_Jadwal::all();
        return view('kkalender.index', compact('data'));
    }

index.blade.php

<head>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <title>Kalender | Inform</title>
    <meta name="csrf-token" content="{{ csrf_token() }}" />

    <!-- Google Font: Source Sans Pro -->
    <link rel="stylesheet"
        href="https://fonts.googleapis.com/css?family=Source+Sans+Pro:300,400,400i,700&display=fallback">
    <!-- Font Awesome -->
    <link rel="stylesheet" href="{{ asset('AdminLte/plugins/fontawesome-free/css/all.min.css') }}">
    <!-- DataTables -->
    <link rel="stylesheet" href="{{ asset('AdminLte/plugins/datatables-bs4/css/dataTables.bootstrap4.min.css') }}">
    <link rel="stylesheet"
        href="{{ asset('AdminLte/plugins/datatables-responsive/css/responsive.bootstrap4.min.css') }}">
    <link rel="stylesheet" href="{{ asset('AdminLte/plugins/datatables-buttons/css/buttons.bootstrap4.min.css') }}">
    <!-- Theme style -->
    <link rel="stylesheet" href="{{ asset('AdminLte/dist/css/adminlte.min.css') }}">
    <link rel="stylesheet" href="{{ asset('plugins/fullcalendar/css/fullcalendar.min.css') }}">

    <meta name="csrf-token" content="{{ csrf_token() }}">

    <link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/css/bootstrap.min.css" />
    <script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.1.1/jquery.min.js"></script>
    <link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/fullcalendar/3.9.0/fullcalendar.css" />
    <script src="https://cdnjs.cloudflare.com/ajax/libs/moment.js/2.24.0/moment.min.js"></script>
    <script src="https://cdnjs.cloudflare.com/ajax/libs/fullcalendar/3.9.0/fullcalendar.js"></script>

    <script src="https://cdnjs.cloudflare.com/ajax/libs/toastr.js/latest/toastr.min.js"></script>
    <link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/toastr.js/latest/toastr.min.css" />

</head>

<body>
<section class="content">
                <div class="container-fluid">
                    <div class="row">
                        <div class="col-12">
                            <div class="card">
                                <div class="card-header">
                                    <h3 class="card-title">Daftar Data Kalender</h3>
                                </div>
                                <!-- /.card-header -->
                                <div class="card-body">
                                    <div id="calendar">


                                    </div>
                                </div>
                                <!-- /.card-body -->
                            </div>
                            <!-- /.card -->

                        </div>
                        <!-- /.col -->
                    </div>
                    <!-- /.row -->
                </div>
                <!-- /.container-fluid -->
            </section>

<script src="https://cdn.jsdelivr.net/npm/[email protected]/dist/js/bootstrap.min.js"
        integrity="sha384-QJHtvGhmr9XOIpI6YVutG+2QOK9T+ZnN4kzFN1RtK3zEFEIsxhlmWl5/YESvpZ13" crossorigin="anonymous">
    </script>
    <script>
        $(document).ready(function() {

            var SITEURL = "{{ url('/') }}";

            $.ajaxSetup({
                headers: {
                    'X-CSRF-TOKEN': $('meta[name="csrf-token"]').attr('content')
                }
            });

            

            var bg_task = ["bg-teal", "bg-purple", "bg-warning", "bg-muted",
                "bg-primary", "bg-success", "bg-brown", "bg-pink", "bg-info"
            ];
            var calendar = $('#calendar').fullCalendar({
                header: {
                    left: 'prev, next today',
                    center: 'title',
                    right: 'month, agendaWeek, agendaDay',
                },
                editable: true,
                events: "{{ route('kkalender.index') }}",
                displayEventTime: true,
                eventRender: function(event, element, view) {
                    if (event.allDay === 'true') {
                        event.allDay = true;
                    } else {
                        event.allDay = false;
                    }
                },

                selectable: true,
                selectHelper: true,
                select: function(start, end, allDay) {
                    $('#dari').val(moment(start).format('YYYY-MM-DD HH:mm:ss'));
                    $('#sampai').val(moment(end).format('YYYY-MM-DD HH:mm:ss'));
                    $('#addModal').modal('toggle');

                },
                eventDrop: function(event, delta) {
                    var start = $.fullCalendar.formatDate(event.start, "Y-MM-DD");
                    var end = $.fullCalendar.formatDate(event.end, "Y-MM-DD");

                    $.ajax({
                        url: SITEURL + '/fullcalenderAjax',
                        data: {
                            title: event.title,
                            start: start,
                            end: end,
                            id: event.id,
                            type: 'update'
                        },
                        type: "POST",
                        success: function(response) {
                            displayMessage("Event Updated Successfully");
                        }
                    });
                },

                events: [
                    @foreach ($data as $value)
                        {
                            kategori: '{{ $value->kategori }}',
                            judul: '{{ $value->judul }}',
                            dari: '{{ $value->dari }}',
                            sampai: '{{ $value->sampai }}',
                            className: bg_task[Math.floor(Math.random() * bg_task.length)],
                        },
                    @endforeach
                ],

                eventClick: function(event) {
                    var deleteMsg = confirm("Do you really want to delete?");
                    if (deleteMsg) {
                        $.ajax({
                            type: "POST",
                            url: SITEURL + '/fullcalenderAjax',
                            data: {
                                id: event.id,
                                type: 'delete'
                            },
                            success: function(response) {
                                calendar.fullCalendar('removeEvents', event.id);
                                displayMessage("Event Deleted Successfully");
                            }
                        });
                    }
                }

            });

        });

        function displayMessage(message) {
            toastr.success(message, 'Event');
        }
    </script>
</body>

this is my route

Route::get('/kkalender', [K_JadwalController::class ,'index']);

your help means a lot to me, thx