Hi, you use gitlab group Path when get gitlab top level groups, this cause errors because ghorg doesnt found all groups, gitlab uses id instead of path for this api calls. You should use group ID, as you can see on go-gitlab function:

• https://github.com/xanzy/go-gitlab/blob/main/groups.go#L258

And on gitlab api documentation:

• https://docs.gitlab.com/ee/api/groups.html#list-a-groups-projects

I patch your code to use ID and it works fine on my gitlab instance with 480 groups and 1250 projects.

This is related to #159 as you can see on the last comment.

Ill prepare a pull request today.

Thanks for your work!