I just got the beer quest (drink 12 beers) and drank 4. But then the quest didn't show up with my pet rock. I was at my house at this time. Then I left my house and got the quest again, but still have 12 to drink.
same thing sort of happened to me, I have to drink 12, i drank 10 and a day or so later drank 4 more and i still haven't completed it, it showed me with needing to drink 2 more