Headers (not headings) are an attribute of Sections.

Each Section can have up to three different headers. Double-click in one of your headers and see if it says "Header" or "First Page Header" or "Even Page header" in the right-bottom corner.
If so, you need to copy the text from the header that you want into this blank one. Or, you can get rid of the different headers in the section.


Different Sections can have different headers from those of other Sections. If you have multiple sections, check the settings for Link to Previous or Same as Previous in your headers. If they are not linked and you want them to be linked, click on the appropriate button.


Sections / Headers and Footers in Microsoft Word 2007-2013

This can be confusing but has been how Word has worked since at least Word 97. It allows a great amount of flexibility since people often want different headers in different sections or on even and odd pages (mirror pages). They almost always want the first page to be different.

People sometimes change the section without realizing that they have done so. A frequent way this happens is if the number or placement of columns is changed, page margins are changed, or the layout has changed from portrait to landscape or back. Sometimes people change margins when what they really need to change is the paragraph "indent."