Why is the data in the table not changing. UPDATE command - php?

Question

PHP

Why is the data in the table not changing ? UPDATE command - php

Handler code:

$vidreds = $_POST['id'];//
$vstatus = 'novisible';

$link->set_charset('utf8');
$sql = mysqli_query($link, "UPDATE `singles` SET M=('$vstatus') WHERE id='$vidreds'");

Form code:

<form action="editfilms.php" method="post">     
                        <tbody>
                            <tr>
                                <td>
                                    <div class="main__table-text" name="<?php echo $film["id"]; ?>"><?php echo $film["id"]; ?></div>
                                </td>
                                <td>
                                    <div class="main__table-text"><?php echo $film["title"]; ?></div>
                                </td>
                                <td>
                                    <div class="main__table-text main__table-text--rate"><i class="icon ion-ios-star"></i> <?php echo $film["rating"]; ?></div>
                                </td>
                                <td>
                                    <div class="main__table-text"><?php echo $film["genre"]; ?></div>
                                </td>
                                <td>
                                    <div class="main__table-text"><?php echo $film["views"]; ?></div>
                                </td>
                                <td>
                                    <div class="main__table-text main__table-text--green"><?php echo $film["M"]; ?></div>
                                </td>
                                <td>
                                    <div class="main__table-text"><?php echo $film["date"]; ?></div>
                                </td>
                                <td>
                            </tr>
                            <button type="submit">YES YES YES</button>
                        </tbody> 
                    </form> <?php } ?>

In echo $film["id"], the ID of the line is passed, which is passed to the handler code. Except... column "M" doesn't change to novisible