PHP嵌套不起作用

Question

My code below doesnt seem to work. ANyone can help with the reason? It checks for the first variable $editID, but the next one '$key' doesnt work.

Every help will be greatly appreciated.

Code below:

<?php
      $editID = $_POST['editID'];
      if (isset($editID)) {
          $key = $_POST['Key'];
          if (isset($key)) {
            $clientName = $_POST['clientName'];
            echo $clientName;
          } else {
            $owner = $current_user->ID;
            global $wpdb; 
            $sql="SELECT * FROM clients WHERE clientID=$editID";
            $clients = $wpdb->get_results($sql);
            foreach ($clients as $client)
            {
              <form role="form" method="POST">
                  <div class="form-group">
                      <label>Client Name</label>
                      <input class="form-control" name="clientName" value="<?php echo $client->clientName;?>" required>
                  </div>
                  <input type="hidden" id="Key" name="Key" value="<?php echo $key; ?>">
                  <button value="submit" type="submit" class="btn btn-default">Update</button>
              </form>
        <?php
            }
          }
      } else {
        echo "Nothing to edit? Please <a href="">go back</a>.";
      }
    ?>