Just wanted to get this into a message in case anyone else had the problem. Xbox live game notifications quit working a couple weeks back on both my and my wife's 822. Annoyed by it a few minutes ago and having a couple of spare mins, I went into the game hub's "3 dot" menu, turned off "sync games requests" and "show game notifications", exited, then immediately went back in and turned them on. To my surprise, notifications immediately started working again. I texted her the instructions, she did them on her phone, and they started working again on it as well.
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