Form not passing variables php

I've made a simple form to deleting entries in a table. When I click the submit button my variables aren't populating. Could someone please suggest why? Here's the html code:

<tr class="tr">
   <td class="td">2</td>
   <td class="td">01/05/2017</td>
   <td class="td">1152</td>
   <td class="td">1270</td>
   <td class="td">1125</td>
   <td class="td">855</td>
   <td class="td">1078</td>
   <td class="td">865</td>
   <td class="td">1730</td>
   <td class="td">1255</td>
   <td class="td">
      <form action="delete.php" "method="post">
         <input type="hidden" value="2" name="id">
         <input type="hidden" value="zjl1nl_asia" name="region">
         <input type="submit" value="Delete" class="delete_button">
      </form>
   </td>
</tr>

and the receiving php

<?php
function secure($var){
    $var = stripslashes($var);
    $var = strip_tags($var);
    $var = htmlentities($var);
    return $var;
}
    //Connect to database
    $hn = "localhost";
    $db = "XXXX";
    $un = "XXXX";
    $pw = "XXXX";

    $conn = new mysqli($hn, $un, $pw, $db);
    /* check connection */
    if (mysqli_connect_errno()) {
        printf("Connect failed: %s\n", mysqli_connect_error());
    exit();
    }

$id = secure($_POST['id']);
$region = secure($_POST['region']);

echo "<p>id: $id<br>region: $region</p>";

$query = "DELETE FROM $region WHERE id=$id";
echo $query."<br>";
$result = $conn -> query($query);
if(!$result) die ("Error: ".$conn->error);

$conn->close(); 

?>

When I echo the variables to screen they show no values. Looking in the address bar however I can see for example: www.example.com/add/delete.php?id=6&region=zjl1nl_asia

Does anyone know why the variables aren't populating?