I produced an invoice with several lines.
When sent to print, 4 pages came out.
Page 1: blank
Page 2: Heading
Page 3: Body (the lines)
Page 4: Total and notes.
Solved by clicking Print > right click Print Preview and shrinking to fit (77% in this case).
This does not happen when I have fewer lines.
My only change to the invoice template was reducing the size of the logo in half.
Maybe someone has a better solution.