API_callback does not fire on successful purchase. How to be?

Question

Classmates

I ran into such a problem: a purchase of goods is made in the OK application, moreover, without payment confirmation. A dialog is shown on the OK side stating that the purchase was successfully completed. The dialog has a large "CLOSE" button, when clicked, API_callback is called with the "showPayment" method. But the window still has a "cross" as a button to close the window, and if you close through it (or by clicking on the background), then there is no API_callback and, as a result, there is no way to process the payment on the client.
As far as I know, this problem has been around for a long time. Can you please tell me if it is planned to be solved? All the same, payments in applications depend on this.

Answer 1

There is a problem, but we will not deal with it in the foreseeable future.
In addition to the client callback, there is also a server callback, so you can receive a notification from your server about a successful purchase.