I have a had a book entitled Unknown Princess in KPD for approximately two years. A marketing adviser suggested I should alter the title to An Unknown Princess and add a subtitle. The great rep at Createspace assisted me to do so without charge. The change also required me to make a slight change in the interior and submit an adapted cover. Now both books, each with its own ISBN, appears on Amazon and the Bookshelf. Also, the book was previously published as The Midwife's Secret with yet another ISBN and reviews which I was at one time told would transfer but do not appear on either newer version. Of the new versions, one displays with the new title and the othrs does not. I truly would love it if only one book was live on Kindle, not two, and of course, prefer the one with the correct title on the cover. If the reviews from the original would transfer, that would be great, but that is not the critical issue.
It might have been simpler if you had replaced the old version with the new one and marked it as a third edition. At this point, you need to go to your bookshelf and unpublished anything you do not want to be published.
if you do not want the old listings to appear as separate "out of print" books, mark the version you want as a later edition. Then email KDP support and ask them to merge the listings as editions of the same title.