@Ferry Van Baar
Thank you for your post!
If you're having issues adding a verified publisher to your app registration, and have received the below error message, this is a known issue that engineering is working to resolve. We don’t have a specific ETA yet, but are hoping to have one soon.
Error Message:
"message": "A verified publisher cannot be added to this application. Please contact your administrator for assistance."
You can continue to follow the issue here:
Publisher verification - Unable to add publisher
Add Troubleshooting steps for UnableToAddPublisher error message
Not able to add MPN ID to App registration
If your issue is related to receiving a different error message, I'd recommend following our Troubleshoot publisher verification documentation or creating a support request so our engineers can take a closer look into your environment.
If you need assistance or would like to work with me in creating you a one-time free technical support request, please let me know.
Thank you for your time and patience throughout this issue.
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