Cannot download from Package registry with personal access token

Package registry

Hello everyone,

I am having troubles trying to download a PyPi package from the Package registry of GitLab 13.3.0-pre with a personal access token. I am running this
pip install pyARG-dep --index-url https://__token__:<your_personal_token>
as documented here, with a personal access token with api rights.

But I am getting this error message:

Looking in indexes: https://token:****
Collecting pyARG-dep
ERROR: Could not find a version that satisfies the requirement pyARG-dep (from versions: none)
ERROR: No matching distribution found for pyARG-dep`

Does anyone have some clue why I am getting this? Is it a problem with my token? Or is the package somehow not available in the registry?