Issue Summary

Requests authenticated via Bearer Token (OAuth 3LO Authentication) fail with 401 error codes, returning "Unauthorized; scope does not match" even if the scope includes the necessary permissions.

Steps to Reproduce

1. Configure an OAuth app (https://developer.atlassian.com/cloud/confluence/oauth-2-3lo-apps/)
2. Ensure that scope includes the necessary Granular Scopes to access the desired endpoint (i.e. "read:attachment:confluence" for attachments)
3. Run a request authenticated with a valid token to retrieve attachments (Get Attachment by ID - API v2)

Expected Results

Attachment details are returned

Actual Results

401 "Unauthorized; scope does not match" is returned

Workaround

This does not happen when using REST v1 endpoints.

Also, if the v2 endpoint is preferred, it is still possible to authenticate requests using Basic authentication.