php form variables are not included in email

De markup (HTML)

<form method="" name="myemailform" action="email-form.php">
  <div class="form-group">
  <input type="name" class="form-control form-control-white" id="name" placeholder="Uw naam" name="fullname" required/>
  </div>
  <div class="form-group">
  <input name="email" type="email" required class="form-control form-control-white" id="email" placeholder="Email"/>
  </div>
  <div class="form-group">
  <input type="message" class="form-control form-control-white" id="message" placeholder="Bericht" name="message" required/>
  </div>
  <input type="submit" class="btn btn-o-white" value="Verstuur"/>
</form>

email-form.php

<?php
  $Subject = 'ingevuld formulier op de website';
  $webmaster = 'info@xxxxxxxxrs.be';
  $emailfield = $_POST['email'];
  $namefield = $_POST['fullname'];
  $messagefield = $_POST['message'];
  $body = <<<EOD
<br><hr><br>
Email: $emailfield <br>
Naam: $namefield <br>
Bericht: $messagefield <br>
EOD;
  $headers = "From: $emailfield\r\n";
  $headers .= "Content-type: text/html\r\n";
  $success = mail($webmaster, $Subject, $body, $headers);
echo "Bedankt voor uw bericht! Klik <a href='http://www.saimibauters.be/index.html'> hier </a> om terug te gaan!";
?>

EDIT: mail adres van webmaster veranderd, anders zullen email harvesters een vroege Sinterklaas hebben. Normale adres gebruiken in de code.