I often have a local server running on port 8000, which prevents me from using the web auth for the CLI until I stop the server. Please check that port 8000 is not in use before starting the server, and if it is, choose another port instead. Alternatively, you may want to just choose a different port instead of 8000 to use, maybe a random 5 digit port. Even if it's hardcoded, that would be much less likely to cause issues than a frequently used port like 8000.