Your sample doc has 3 sections in 5 pages. Each section needs to be examined to fully understand what is going on but lets jump to the last section which is where your stated issue is seen.

Section 3 covers pages 3-5. Section 3 is set to have both a Different first page and Different Odd/Even pages - which means that Section 3 has three different headers and footers. I can see you have added a styleref field to the First Page Header of Section 3 but you haven't added it to the Even Page Header of Section 3 (which is linked to the Even Page Header of Section 2).

I am not sure why you felt you needed the section break after the first page of the Geneology section of the document so I would remove that last section break and then pay attention to which header I was worried about.

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Andrew Lockton
Chrysalis Design, Melbourne Australia