I am integrating the Express Checkout API, and there is a problem with updating notification for any transactions you have made. How will PayPal send me the notification?
If a transaction has not been approved at this time, and after 24 hours it is completed, how do I get this update?
In order to receive information, both feedback after checkout and later (in case of more time-consuming analysis), you need to implement a Controller that will be accessed by Paypal at a later time, in assíncrono process. >
This is called Instant Payment Notification , which happens in step 2 and 5 of the following stream:
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