A family of Microsoft spreadsheet software with tools for analyzing, charting, and communicating data.
This is what they say.....(it is not exactly what i'm experiencing but very close)
Fill cell formatting does not render correctly after adding a header in Page Layout view in Excel 2016
Applies To: Excel 2016
Last updated: September 27, 2017
ISSUE
When in Page Layout view, applying a fill formatting such as a pattern style to a cell or table does not render correctly after adding a header or a footer to the spreadsheet. You may see a black background or other formatting issues.
This issue impacts Version 1708 (Build 8431.2079).
STATUS: WORKAROUND
We are currently working on a fix. In the meantime, you can remove the header and or the footer from the spreadsheet for the fill formatting to render correctly.