Test in-app purchase: “android.test.purchased” did not work now

Hi everyone, i found a sample project with make in-app purchase here, with OpenIAB plugin: https://github.com/GrimReio/OpenIAB-sample-game
Few days ago, i had tested the project with Google id like "android.test.purchased" and it successfully show me the fake money to test. I tested again and again, and it seem no bug apears.
But just from yesterday and til today, when i tested with that id, it still show "Fake money", but return "Google has stop...", then the purchase became failed.
I tested again in 2 other phones, but it returned the same result. I tried with Soomla plugin, but can't fix the problem.
Beside that, i switched to iOS platform, and it show in-app purchase well.
So does it a error by Google, or Google has changed something with in-app purchase?