Customized Put up Sort add_rewrite_rule

I’ve a small element in a wordpress web site, I want to modify the url of the sinlge put up of a particular sort of content material:

• post-type = ebook

• Present permalink = web site.com/ebook/title-book

• I need
  to put: web site.com/ebook/customized/title-book

  add_rewrite_rule(
  ‘^ebook/[^/]+/([^/]+)/?$’,
  ‘index.php?post_type=ebook’,
  ‘prime’
  );

I’ve searched and tried all the pieces and it has not labored for me, please if anybody has any thought methods to do it.

Thanks