A user named 02fentym had posted a question named Modal Cadence Options which was a complete duplicate of his / her older question named Cadences for Modes. Do we accept such duplicate questions here?
No, a duplicate question is a duplicate question. No matter how old the question is ( I guess you are referring to this: Cadences for Modes and this: Modal Cadence Options ), you can vote to close it, like you have.
It's not uncommon for users that aren't familiar with the way this site works to post their questions twice, especially if they haven't got a (satisfactory) answer.