There are achievements that appear as locked, even though you already have them, meaning they appear as duplicates.
Example: Play more than 2,500 cards (it's both unlocked and locked)
Earn 10k chips in a single hand (it's both unlocked and locked)
Although with the last one, it's repeated, but the name is 1000k even though the description says 10k chips.
Then it's repeated, but with the name 100k, however, the description says 10k again.
And with the 2,500 card achievement, it appears duplicated, but with a different name in the locked one. The one I have unlocked is called "Card Player," and the locked one (with the exact same description) is called "Savings."
That's all, it seems strange to me.