MS Graph Authorization issue (Status code 401) - Power Automate Flow for Copilot Studio

Hi Folks,

I am trying to develop a MS Power Automate Flow that can post QMS documents information to Copilot Studio bot based on users' question. I am using 'Create text with GPT using Prompt" to extract users' intention about documents from their natural language. Then use HTTP connector to post the results to Copilot Studio bot. I have done all the steps:

1. Registered App in Azure Portal

2. Granted Sites.Selected (Read) permission to my app so that it can read the information from QMS document library in SharePoint. We only want the app permission related to subsite not the whole site.

The issue I am facing is that the HTTP action is still showing unauthorized Status code 401.

Could you guide me if there is something incomplete or insufficient? Many thanks.

After running please see below error:

Best regards,

perlite77