Extra space between sections means invisible line breaks have been inserted after the text (caused by hitting the Enter key at the end of a line).

It's easy to remove them.

1. Open your resume and click the Edit button under the section that has extra space.
2. Place your cursor at the very bottom of the text box (you may need to drag the right-hand scroll bar down to reach the bottom).
3. Use the Backspace or Delete button to remove the extra spaces until the cursor is right at the end of the text, with no space afterwards. Click Save.

This process gets rid of the invisible line breaks and should solve your spacing problem! (Click Preview to make sure.)