Are you pressing Enter at the end of each line? In that case, you are actually creating new paragraphs and Word might be adding Spacing After (or Spacing Before) to text. You should only press Enter when you in fact want a new paragraph; let Word wrap the text lines automatically instead.

To change the defaults for Line Spacing and Spacing Before/After, you can do the following: Create a new, blank document, for example by pressing Ctrl+N. In the Styles pane (Ctrl+Alt+Shift+S), click the Manage Styles button. On the Set Defaults tab, specify the desired settings. Before clicking OK in the dialog box, select "New documents based on this template."

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Stefan Blom
Microsoft Word MVP

Microsoft 365 apps for business
Windows 11 Professional