Google Play not working with Galaxy s6, fine with other devices

I’m developing my first mobile game for android and I’ve got 4 testers, one has an s6 and although they can connect with [Show External Login UI] and log in they can’t upload achievement progress or leaderboard scores, those nodes output [FAILED]. He also can’t view leaderboards or achievements, basically he logs in fine, stays logged in and never disconnects, but can’t do anything. None of my other testers (using Galaxy s7 and Galaxy s5) have this issue so I have no idea why the s6 is having issue. I don’t even know if it’s an s6 thing or just this testers phone.

I’m pretty stumped, anyone have an idea of what the problem could be?

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je trouve que ce que tu di est nul car moi ca marche tres tres tres tres tres tres tres tres tres tres tres tres tres tres tres tres tres tres bien !!!

Issue was in the Google Play Console, nothing to do with UE4.