Why am I getting an [ERROR: Cannot refresh achievement : VALID_BUT_STALE] response when I call PlayGamesPlatform.Instance.IncrementAchievement?

Hi everyone, I'm using the GooglePlay Plugin for my android mobile game and am receiving the following response when incrementing achievements:

• *** [Play Games Plugin DLL] 02/23/17 11:45:42 -08:00 ERROR: Cannot refresh achievement CgkIjMiIuf8ZEAIQAw: VALID_BUT_STALE

The twist is that this was working last week. Then I decided to delete my GooglePlay Gamer profile on my test device to test out another feature and started seeing these "VALID_BUT_STALE" responses through LogCat.

Using Unity 5.4.2f2 and Google Play Games Plugin 0.9.36.

Does anyone know why I would receive this status response or how to fix/diagnose it?

Let me know if more information is required.

Thanks!