Not Found error when implementing Oauth2

I am implementing GitHub - googleworkspace/apps-script-oauth2: An OAuth2 library for Google Apps Script. for google sheets.

I am following the Web API Authentication example.

I have created the Example Authorization Call:

https://api.nuki.io/OAuth/authorize?client_id=????????????????????&response_type=code&redirect_uri=https%3A%2F%2Fscript.google.com%2Fmacros%2Fd%?????????????????????????????????????????????????????????????%2Fusercallback&state=ADEpC8x90b4PfQCDzNq_DCw-cNCPDHcKuL3yn5TFuD0TrApmDoLV-Kz57Jlj3sUTHzPYE0vkhI6rLoig8J6duMK7RYHx3wHLqbhGSEV2Ma3WDqb4ywxVtP7WoZcZxezKSkkahmE6nZvx1mNnVbDn8NWAZiyrleoUG-YyKXjYNXtZsh3d41bAC_x0YKsImVd8sgMqM_GApREJnPybT3Yh8363LckL1ymzNGtS48NAg0iew5BAMenuB-gbSW0-14UvP5wl9j9mDAfGln_fqRjA2WOO7rlmo6DqVg&scope=smartlock.auth

When I run this I get the following error!

image