How to test payment ok?

Good day, writing payment for goods in the game ok'AMI.
Trigger FAPI.UI.showPayment screen is displayed, saying that I want something and buy it, everything is OK, click "Yes", the logic at this point, the classmates got to pull my server at the url specified in the app settings. They don't twitch, and a simple output window "payment system on prevention." According to the description in the documentation this message is displayed if somewhere something went wrong. But how do you know where, what and how? No the logs do not see that happening, it is unclear how to know that not so made that? Spasiuk.
April 4th 20 at 00:56
1 answer
April 4th 20 at 00:58
there is a sandbox

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