Hello Rachel,

Your responsive viewports use a separate header which you need to define in Step 1 General Settings > Template Style > Responsive Template Structure...  select 'Header' from the 'Page Section' drop-down menu.

You can find more information in the WebSite X5 help file:

http://help.websitex5.com/en/v12/pro/index.html?responsive_template.htm

Kind regards,

Paul