Header Element Options not showing in customizer

Hello
I want a header for my entire site.
I just want to use the navigation as the header element for the site. I have a logo and site title on the homepage. However, the header element options do not appear in the customizer as shown in the instructions. https://docs.generatepress.com/article/navigation-as-a-header/

In particular, there is no option to activate 'Use Navigation as Header'

All I have in my customizer for Appearence>Layout>Header are as shown in the screenshot here https://snipboard.io/7M3FxO.jpg

I have GP Premium installed and the Elements module activated.

Thank you for your help.