Google payment error prompt: error retrieving information from server [df-aa-20]

Google in-purchase payment test, released the beta version for testing, download and install after payment error prompt: error when retrieving information from the server [df-aa-20]
The reasons may be:
1. This product does not create in-purchase goods. (It takes time for the creation to take effect, so you can wait 10 minutes to try again)
2. The app was not released in the Google Play store, at least in alpha.
3. The app or developer account is blocked.

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