Check if header has been enabled in Header
tab of Format
>Page
. In this case, uncheck the box.
To have an idea about what is editable and what is not in a document, enable View
>Formatting Marks
. Pilcrows (something like a mirrored P) display when you have a user-editable paragraph. In your context, this will be the header.
By the way, it is a good idea to keep View
>Formatting Marks
always on. This gives visual clues on screen and these clues never print.
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