Hey Brittany! Could you give examples of any achievements you know you completed for sure, but were not marked as such? Any achievement achievable in Single Player, should also be achievable in Multiplayer.
If you could describe the situation and the achievement in case, we'd love to investigate further and assist you with this. Thank you!

Simple ones like marking on the clue sheet being one of them.
I was playing with the app with friends through local play (I was streaming this online) and I only got the one achievement which required friends. It also wasn’t recording my wins during this mode either.
I tried it with single player and all my stuff was recording instantly. The wins, the more simple stuff like taking notes in the clue sheet etc.