We had a working plugin for uploading apk/aab to the store, but some time ago it broke. Have you rolled out some kind of update or have there been changes in the API?
The session and file upload are successful, but at the /seller/contentUpdate stage we receive an error.
Failed request: url - https://devapi.samsungapps.com/seller/contentUpdate,
code - 403,
body - {"from":"seller","body":{"ctntId":"00000NNNNNNN","contentStatus":"UNDER_TEST_CONFIRMATION","httpStatus":"FORBIDDEN","errorCode":"4111","errorMsg":"Content type is not valid"},
"message":"Request failed with status code 403"}