Go does not find the repository in a subgroup

Go cannot find a repository that is inside a subgroup, how can I do it?

I have two repositories both really have the same content since it is for the example and they fulfill the same characteristics. They are repositories where their visibility is private, their default branch is main and they have a tag. But when importing them in go or trying to get them, it is not possible for the one that is in a subgroup:

What I am doing if it is possible? Or actually it is not possible, I already tried to set GOPROXY and GOPRIVATE environment variables, also with SSH keys.

also provides CI/CD integration tips how to use SSh instead of https.