Following my tests, the API endpoint is functioning excellently. The test results are as follows:
Please verify by reviewing my tests, particularly whether the section_id is accurate and if a page exists under the respective section.
At the same time, you can also use the following request to query all pages, find your corresponding page, check the parent section id and name.
https://graph.microsoft.com/v1.0/me/onenote/pages
More information about the API can be found at this link:
https://learn.microsoft.com/en-us/graph/onenote-get-content
Hope this helps.
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