Helvetica Neue does not have an official variable font. If you see HelveticaNeueVariable.ttf on GitHub, it is a hacked, unlicensed, or corrupted file. helvetica neue font family github

GitHub is great for code and config , not for distributing proprietary fonts. For open-source alternatives, search GitHub for "open source helvetica alternative" or "sans-serif font stack" . Helvetica Neue does not have an official variable font