I'm having a problem testing the IPN in Sandbox mode.
I've tried it in two ways:
Mailing the url_notification by payment preferences. When I do this, I call my notification url, but when I go to find the payment information, either through getPaymentInfo or by doing a GET to link (sending the necessary parameters), I do not get results.
I also tried removing the url_notification from the preference and configuring it in my MercadoPago account. When I do it this way, I do not even call my notification URL.
Any help?