This question already has an answer here:
- Circular duplicates strike again 1 answer
This suggestion is perfectly correct: these are exactly identical questions asked by the same user. However, there's not much point in closing question A as a duplicate of B, since question B has already been closed as a duplicate of A.
Yet the close vote remains, doing nothing but wasting reviewers' time.
This is not the first time I've seen this happen, so I'd like to suggest that the Stack Exchange software should do something about it. In particular, I'd like to suggest the following feature:
When a question Y is closed as an exact duplicate of another question X, any votes or flags to close X as a duplicate of Y should be automatically discarded.
Actually, I'm kind of surprised that the SE software doesn't do that already. If anyone else thinks that this constitutes an actual bug, feel free to retag it.