<div class="form-group tanggal_daftar">
            <label class="col-form-label">Tanggal Daftar</label>
            <input type="text" name="tanggal_daftar"  class="form-control tanggalinput">
          </div>
          <div class="form-group propinsi">
            <label class="col-form-label">Propinsi</label>
            <select data-plugin-selectTwo class="form-control select2" name="propinsi" id="propinsi">
                <option value="">Pilih Propinsi</option>
                <?php foreach ($propinsi as $kat): ?>
                <option value="<?php echo $kat->id;?>"><?php echo $kat->name;?></option>
                <?php endforeach; ?>
            </select>
          </div>
          <div class="form-group kota_kab">
          <label class="col-form-label">Kota/Kab</label>
          <select data-plugin-selectTwo class="form-control select2" name="kota_kab" id="`kota_kab`">
        </select>
          </div>

--- INI AJAXNYA -----
$('#propinsi').on('change', function() {
            var dataId = $(this).val();
            var $dropdown1 = $('#kota_kab');
            $dropdown1.empty();
            $dropdown1.append($('<option />').val('').text('Pilih Kabupaten / Kota'));
            $dropdown1.select2('val', '');
            $.ajax({
                type: 'GET',
                url: '<?= base_url() ?>admclub/getlevel2',
                data: 'level1=' + dataId ,
                dataType: 'json',
                success: function(response) {
                    $.each(response.data, function(i, item) {
                        $dropdown1.append($('<option />').val(item.id).text( item.name ));
                    });
                }
            });
        });
        $('#propinsi_edit').on('change', function() {
            var dataId = $(this).val();
            var $dropdown1 = $('#kota_kab_edit');
            $dropdown1.empty();
            $dropdown1.append($('<option />').val('').text('Pilih Kabupaten / Kota'));
            $dropdown1.select2('val', '');
            $.ajax({
                type: 'GET',
                url: '<?= base_url() ?>admclub/getlevel2',
                data: 'level1=' + dataId ,
                dataType: 'json',
                success: function(response) {
                    $.each(response.data, function(i, item) {
                        $dropdown1.append($('<option />').val(item.id).text( item.name ));
                    });
                }
            });
        });