I’ve reached the final stretch of a children’s quiz-game and everything works—except Google Play Games Sign-In. Google Sign-In authenticates correctly, so I’m convinced the code base is sound; the headache seems to sit inside the Google Play Console configuration. Here’s what I already know and have done: • SHA-1 fingerprints are in Firebase and the Console. • Firebase Authentication itself is behaving. • Google Play Games Services has been created, linked to the app, and every guideline was followed as far as I can tell. • Internal Play Store test releases still fail to authenticate when I switch from plain Google Sign-In to Google Play Games Sign-In. Where I need your expertise is combing through the Console setup—especially the Google Play Games Sign-In section, OAuth clients, and any hidden switches that might prevent the token exchange. A step-by-step verification of every console screen, SHA-certificate, and test track permission is what I’m after. Once the configuration is corrected I’d like you to run an internal test build, demonstrate a successful sign-in, and leave me with a concise checklist so my team can reproduce the flow for future titles. If you’ve untangled this exact problem before, let’s get the game over the finish line.