Hi @Akarat Gobkuea, we have single sign on already set up between OneNote and Stream. You may however, be experiencing some issues, and I'd like to try and get to the bottom of it. Here are some questions:
1. What OS and OneNote application are you using? Example response: Windows 10, Win32 OneNote App. As a side note, it is possible that the certain version/applicaiton you are using doesn't support this auto login embedded capability.
2. Is the user logged into the OneNote application?
3. Can you try on the OneNote web application with Edge or Chrome to see if that works?