Cannot select `gh-pages` when making a new private nbdev GitHub repo

[hyunjongkimmath]

I was following the steps of the End-to-End Walkthrough (except I made the GitHub repo private instead of public). I got to the Enable GitHub Pages step, but I could not select the Branch setting to gh-pages.

[jan-david-fischbach]

probably your Action did not run through. Can you check? Additionally it might be a good idea to share the repo