Reports

Consider using the region header if you are working in a non-USA hub.
Keep in mind that the User-id should be the admin id not the user you are trying to add.
Try to add only one user using this call: https://aps.autodesk.com/en/docs/acc/v1/reference/http/admin-projects-project-Id-users-POST/ and see if that works… I am maybe not the professional one to answer, but I have tried too many things in the last couple of weeks so I hope my tips would help you.

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