I flagged this question as a duplicate, the flag is marked as helpful. But it didn't get closed, I commented in chat and it's still open.
Close flags are marked as helpful the first time someone close votes. In this case, one user close voted and three others didn't , so the flag was marked helpful even if the post didn't get closed, and the review item was dequeued due to the majority of do-not-close votes.
A "helpful" flag means that the flag had some worth and you should not be discouraged from raising flags in similar cases later on, even if the flag is not acted on. When it comes to close flags, if a user agrees with you, that usually means that the flag has some merit and should be marked helpful.
At first glance, they probably should be closed, but I'd like to see the opinions of other community members on the matter first given that at least three people feel that it is not a dupe.