Stuck

<tbody>
                    <?php
                      $koneksi = mysqli_connect('localhost', 'root', '', 'db_wbcweb');

                      $panggil_db = mysqli_query($koneksi, "SELECT * FROM tabel_barang");
                      while ($row = mysqli_fetch_array($panggil_db, MYSQLI_ASSOC)) {
                        $id = $row['kd_barang'];
                        echo "<tr>";
                        echo "<td>", $row['kd_barang'], "</td>";
                        echo "<td>", $row['nm_barang'], "</td>";
                        echo "<td>", $row['jn_barang'], "</td>";
                        echo "<td>", number_format($row['hrg_jual']), "</td>";
                        echo "<td>", number_format($row['hrg_beli']), "</td>";
                        echo "<td>", $row['jml_barang'], "</td>";
                        echo "<td>
                          <a data-toggle='modal' data-target='#beliModal' data-href='beli_action_barang.php?kd_barang=".$id."'>
                            <button class='btn btn-outline-primary btn-sm'>Beli</button>
                          </a>
                          <div class='modal fade' id='beliModal' tabindex='-1' role='dialog' aria-labelledby='hapusModalLabel' aria-hidden='true'>
                            <div class='modal-dialog' role='document'>
                              <div class='modal-content'>
                                <div class='modal-header'>
                                  <h5 class='modal-title' id='hapusModalLabel'>Pembelian Barang</h5>
                                  <button type='button' class='close' data-dismiss='modal' aria-label='Close'>
                                    <span aria-hidden='true'>&times;</span>
                                  </button>
                                </div>
                                <div class='modal-body'>
                                  <form>
                                    <div class='form-group row'>
                                      <label for='jumlahBarang' class='col-sm-2 col-form-label'>Jumlah</label>
                                      <div class='col-sm-4'>
                                        <input autocomplete='off' type='text' name='jml_barang' class='form-control'>
                                      </div>
                                    </div>
                                    //Disini mas
                                    <div class='alert alert-warning' role='alert'>
                                      Maksimal pembelian adalah ".$id."
                                    </div>
                                  </form>
                                </div>
                                <div class='modal-footer'>
                                  <button type='button' class='btn btn-outline-secondary' data-dismiss='modal'>Batal</button>
                                  <a id='btn-beli'><button type='button' class='btn btn-outline-primary' data-dismiss='modal'>Beli</button></a>
                                </div>
                              </div>
                            </div>
                          </div>
                          <a href='form_edit_barang.php?kd_barang=".$id."'>
                            <button type='button' class='btn btn-outline-info btn-sm'>Ubah</button>
                          </a>
                          <a data-toggle='modal' data-target='#hapusModal' data-href='delete_action_barang.php?kd_barang=".$id."'>
                            <button class='btn btn-outline-danger btn-sm'>Hapus</button>
                          </a>
                        </td>
                        ";
                      }
                    ?>
                </tbody>