The error message AADSTS900561 indicates that the endpoint you are trying to access only accepts POST requests, but a GET request was received instead. To resolve this issue, ensure that your request method is set to POST when making the API call to the specified endpoint. This typically involves checking the code or tool you are using to ensure the correct HTTP method is being utilized.
If you continue to encounter issues, consider reviewing the API documentation for the specific endpoint to verify the required request format and parameters.
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