Action hooks returning old category instead of new category

Question

With some help I created a WP Action to send an email to the author of a post (custom post type) when the category has been changed.

This works ok, except that the function is returning the previous category instead of the current category.

For example, if the post was cat2 and the admin updates it to cat3, the email gets sent saying that your post has been updated to cat2 (the category before the update was made).

I'm completely at a loss with this because these hooks ( added_term_relationship and deleted_term_relationships ) are supposed to fire after the category is updated, not before. So how is it possible that they're sending the previous category instead of the updated current category?

My code:

function notify_object_terms_updated( $object_id ) {
    $post_id   = get_the_ID();
    $userEmail = types_get_field_meta_value( 'your-email', $post_id );
    $newCat    = get_the_category($post_id);
    $ideaTitle = get_the_title($post_id);
    $headers   = array();
    $headers[] = 'MIME-Version: 1.0' . "\r\n";
    $headers[] = 'Content-type: text/html; charset=iso-8859-1' . "\r\n";    
    $headers[] = 'From:XYZ Continuous Improvement <[email protected]>';

    static $did = array(); // This function might fire multiple times for the same object, ensure it only runs once
        if ( ! isset( $did[ $object_id ] ) ) {
            $did[ $object_id ] = true;

     wp_mail( 
        $userEmail, 
        'Your Continuous Improvement Idea - ' . $ideaTitle, 
        '<p>The status of your Continuous Improvement idea titled "' . $ideaTitle . '" has been updated to <strong>' . $newCat[0] ->cat_name . '</strong>.</p>' . '<p>You can view the progress of your idea anytime on the <a href="http://continuous.improvemen.com/board">Continuous Improvement Board</a>.</p>',
        $headers 
        );
    }
}

add_action( 'added_term_relationship','notify_object_terms_updated');
add_action( 'deleted_term_relationships','notify_object_terms_updated');

edit: declared array.

Answer 1

Although the hooks are passing you the ID of the changed object in the parameter $object_id, you aren't using it and are calling get_the_ID instead which will give you the ID of the current loop item.

Try changing your uses of $post_id to $object_id instead.