title: WooCommerce Subscriptions - Action hook not triggered on renewal
body: <p>I have made a custom function which adds account funds (£40) to a user's account when their subscription payment is successful.</p>
  
  <p>The problem I have is that the hook doesn't seem to trigger, when the renewell happens the funds are not added to the account.</p>
  
  <p>I enabled debugging in Woocommerce and pushed the renewal manually within the cron management, when I do this the function works and the funds are added to the account.</p>
  
  <p>Here is my function (functions.php);</p>
  
  <pre><code>add_action('processed_subscription_payment', 'custom_add_funds', 10, 2);
  
  function custom_add_funds($user_id) {
  
      // get current user's funds
      $funds = get_user_meta( $user_id, 'account_funds', true );
  
      // add £40
      $funds = $funds + 40.00;
  
      // add funds to user
      update_user_meta( $user_id, 'account_funds', $funds );
  
  }
  </code></pre>
  
  <p>----- SOLVED -----</p>
  
  <p>I needed to up the memory limit on wordpress, the IPN url was Fatal Errored/exhausted</p>