Remove Cookie while logout

Remove_cookie.php

<?php 
function your_function() {
  if (isset($_COOKIE['nextend_uniqid'])) {
    unset($_COOKIE['nextend_uniqid']);
    setcookie('nextend_uniqid', '', time() - 3600, '/'); // empty value and old timestamp
}
}
add_action('wp_logout', 'your_function');
?>