I just happened to read the instructions for Duplicate Closure today. It says:
This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.
See the image to be convinced:
It asks the user to ask a new question. So far we used to ask the users to edit the question and flag for moderators/post on meta to get it reopened.
Has there been a change in policy?