Try Ctrl+A, Ctrl+Q, Ctrl+Spacebar.


I do not know that this will help but it might.


The spacing can be caused by the font, and by paragraph formatting. It can also be caused by page alignment but this is rare. A document will have a set of default fonts which are a part of the Theme. Default Paragraph Font Explained


When you are applying your styles, how are you doing that?


The only way I know to delete all formatting in imported text is to paste as text only. There is no such thing as deleting all formatting at the document level.