Someone unlocked the achievement in the game, but it was not showing on the profile, so do I.
Now I know how to solve it:
1. Uninstall the game, and you'd better restart the phone.
2. Reinstall the game and disconnect the wifi.
3. Start the game and open "Achievement" to see whether "Combo User" is unlocked.
4. If the achievement is not unlocked, you can play Training-Memory-Direction, when you get 30 combo, it will pop, then you can connect the wifi to sync the achievement.
5. If the achievement is still unlocked, please report it here, let me think about it again.