Because you have cleared 2 achievements (which are supposedly working) but did not get them, I’d lean more on the fact that it is not an achievements issue but rather one of the following:
You are not properly connected to Bnet to register the achievements.
You have previously used a cheat and has bugged the game. Restarting the client will usually solve this problem.
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If none of the above applies to you, then considering that this is the 2nd post, it might actually be a bug:
Hi, sorry if I have a grammar problem, I try to write in english.
The problem is: All Nova achievements are unlocked, normal and 10°aniversary. I just passed the first level, 5th time, and I don’t receive anything (Including the achievement that you win when you “Just win” the level). It’s a bug or just only me? I’m log-in all time and I did all requirements. Can someone help me? Thanks.
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Here is a Blue’s post relating to achievements not updating. I am unsure if this will solve the issue:
Hey there,
There’s one thing that I’d recommend trying. Delete the Blizzard cache folder to clear out the Starcraft II profile/achievement cache and then re-launch the game so it will be recreated.
If that doesn’t do it then I’d recommend reporting it as a bug over on #bug-report , since it should definitely be giving you new achievement credit for completing those missions on Hard.