If you are testing through MSP's Business Id then it will not work. Try using the Business Id of the BCP account, where you have added this oAuth details.
Siddhartha_paul
Users receive reputation points by contributing quality content to the forums.
Posts include post and replies published on the forums.
Post authors can mark replies as Accepted to indicate successful solutions.
Apple Developer Forums admins can mark replies as Apple Recommended to indicate an approved solution
Post
Replies
Boosts
Views
Activity
Facing the same problem. Did anyone get any solution for this?