This happened to me when I publish my Pandora article. I wrote a blog post on Integral Life. There was so much traffic and response to it that I decided to publish it as a hub on Hubpages. The traffic here was amazing, but it was marked as a duplicate and the score was dropping and dropping. In order to save it here I deleted it at the Integral life. But the score went down again. I re-wrote it and published in a new shape. Only then the label "duplicate" disappeared. The score reflects the traffic now. You probably have no choice, but to re-write it. Since you probably cannot remove it from the other page, changes, including the title, will have to be considerable. I would probably save the text, delete the article, and publish a new one, with new title and the altered text. It looks like much work, but this is probably the only way to receive credit for a good work.
Good luck! Dominique