How to reposition body text in a document

I have a document that was originally based on the Invoice template. This has the body text in a right hand column, and somehow this is now misplaced on the page. Turning on View > Show Layout shows the bounding box of the body text, and it is placed too far below the header. If this expands to a second page though, it actually overlaps the header.

I can't figure out how to modify the layout and reposition these boxes where the body text is placed. I also don't see how the second page is managed, as it is also incorrect.