I had a similar problem. Here’s how I solved it: I deleted all Python-related versions in Windows 11 installed applications. The model already has its own “python-3.6.8” files in the “DeepFaceLab_NVIDIA_RTX3000_series\_internal” path. Python versions installed on Windows 11 break the pyton version of the model. I think the problem will be solved if you remove the Python-related versions of Windows installed applications. However, considering every possibility, back up the installation files of these Python version files to your computer before removing the installation files of Python versions.
On Windows, install only the python-3.6.8 version that is the same as the python version of the model.