After much frustration with the same problem it turns out that I had different versions of Python installed in different computers and so, when I tried to activate a venv created in one computer, it would fail in another because it could not find the base python executable

Though this solution may be helpful to others: the issue I had is that I edit the project from various computers (have the repo stored in OneDrive and can easily pick up work at home, work or laptop seamlessly). And so the problem kept recurring - when I tried to rebuild the virtual env to fix the issue in one computer, it would create it elsehwere!!