It is likely that you typed your whole book with double-spacing for the lines, like you were told to do for manuscripts.  EBooks don't use double-spacing, so we convert the whole thing to single spacing.  We keep extra spaces above the first paragraph of every chapter, and above the first paragraph of every scene-break, using vertical white-spacing for visual impact and clarity of the storytelling or information. 

It is likely that you typed your whole book with double-spacing for the lines, like you were told to do for manuscripts.  EBooks don't use double-spacing, so we convert the whole thing to single spacing.  We keep extra spaces above the first paragraph of every chapter, and above the first paragraph of every scene-break, using vertical white-spacing for visual impact and clarity of the storytelling or information.