Testing the Instant Payment Notification URL

In order to make sure that the Instant Payment Notification functions correctly, follow these steps:

Make sure that your URL is available online: your shop must neither be in maintenance mode nor be protected by an .htaccess file.
Make sure that your notification URL is available without any redirection.
1. To do this, paste your notification URL to the address bar of your browser and launch the search.
2. Make sure your URL did not change.
  If your URL has changed, for example from "http" to "https" or "http://abc.net" to "http://www.abc.net", it means a redirection is active on your website. Then, copy the URL from the address bar and modify the URL filled in the configuration of all notification rules.
Make sure that the “Automatic redirection” option is disabled in the payment module settings.
Check that the Instant Payment Notification URL at the end of payment is populated in the Merchant Back Office (see above).
Make an order on your website and proceed to payment.
Do not click on "Return to shop" at the end of payment and close the current tab of your browser.
Make sure that the order status is Processing or Pendingin the Magento Back Office.

If the order status is still Pending (pending_payment), this means that the call has failed.

If the payment gateway is unable to access the URL of your page, an e-mail will be sent to the shop administrator.

It contains:

The HTTP code of the encountered error
Parts of error analysis
Its consequences
Instructions to resend, from the Merchant Back Office, the notification to the URL already specified above