add_post_meta not working

I am using add post meta function to save some data and its not working

<?php
//include ‘../../../wp-blog-header.php’;
$unique = “true”;
$pageID = $_GET[‘postID’];
echo “pageID:”;
echo $pageID;
echo “</br>”;
$num_posts = $_GET[‘num_posts’];
echo “num_posts: “;
echo $num_posts;
echo “</br>”;
$num_posts_meta_key = “num_posts”;
add_post_meta($pageID, $num_posts_meta_key, $num_posts , $unique) or update_post_meta($pageID, “num_posts” , $num_posts);
?>

Can someone help me out?