See attached which has a Document Property Content Control on Page 1. This control is also in your continuation header. This also will change the Title document property in your document summary.
You had two headers in your document, a first-page header which was not displayed as well as the continuation header. I do not know whether that was the cause of your problem. The Document Property Content Control's use in this fashion is described on Greg Maxey's Page
Repeating Data (Populating Multiple Like Fields)
It is a long page because there are a number of ways to repeat things in a document. Search for "Document Property" to get to the discussion of this one.