Are the articles real duplicates, or is the same article just showing twice on the site? Edit one article and make some changes. If both instances change, then there is only one article but it is showing twice.
In that case, your theme template will require modification. You may need to hire someone to do that work. You can post a job request at jobs.wordpress.net.
If there really are two articles, not one showing twice, delete one like this:
- Log in as an admin
- Edit the article
- Click ‘Move to trash’
