Update or delete SQL row based on radio button selection PHP

Question

I'm trying to update/delete a SQL row based on the value of a radio button using PHP.

My code looks like the below and so far, when i click the submit button - it does nothing!

<form method="post" action="?action">
  <?php
  $stmt = $pdo->query('SELECT * FROM reviews WHERE Approved="0" ORDER BY id DESC');

  while ($result= $stmt->fetch(PDO::FETCH_ASSOC)) { 
  $reviewtitle= $result['Title'];
  $rating= $result['Rating'];
  $name= $result['Name'];
  $date= $result['Date'];
  $review= $result['Review'];
  $ID= $result['ID'];
  $counter = ++$counter;
  ?>

  <br>
  <?php echo $reviewtitle; ?><br>
  <?php echo $rating; ?>
  <br>
  <?php echo $name; ?><br>
  <?php echo $review; ?>
  <p>Posted: <?php echo $date; ?></p>
  <p>Review ID: <input type="text" name="IDNumbers[<?php echo $count; ?>]" value="<?php echo $ID; ?>" readonly></p>

    <input type="radio" name="approved[<?php echo $count; ?>]" value="Approve Review"> Approve Review<br>
    <input type="radio" name="approved[<?php echo $count; ?>]" value="Delete Review"> Delete Review<br>

  </div>
  <br>
  <?php } ?>
  <br>
  <br>
  <input type="submit" value="Submit">
</form>

-

<?php
    $CurrentID = "";
    if (isset($_GET['action'])) {
        $count2 = $counter;
        while ($count2 > "0"){
        $CurrentID = $_POST["IDNumbers[".$count2."]"];  
            if ($_POST["approved[".$count2."]"] = "Approve Review") {
                    $stmt = $pdo->prepare("UPDATE reviews SET Approved='1' WHERE (ID=?)");
                    $stmt->execute(array($CurrentID));
            } elseif ($_POST["approved[".$count2."]"] = "Delete Review") {
                    $stmt = $pdo->prepare("DELETE FROM reviews WHERE (ID=?)");
                    $stmt->execute(array($CurrentID));
            }
            $count2 = --$count2;
        }
        echo "<h2> Successful!</h2>";
    }
?>

There are some other bits of code in this however, it seems like the button does nothing at the moment and I'm really not too sure why. I am new to PHP, so go easy please :)

If anyone can see that this is going to go wrong in other ways, please let me know as I haven't been able to test it yet as the button won't work.