Announcement reposted from Amazon Japan:
We’ve identified an issue where some tracking IDs for seller-fulfilled orders aren’t recognized as valid for your Valid Tracking Rate (VTR) calculation.
We apologize for the inconvenience and are working to resolve the issue as quickly as possible.
In the meantime, we’re taking steps to protect your listings. We won’t deactivate account listings if your Valid Tracking Rate (VTR) falls below the 95% threshold, even if you receive an Account Health alert for low VTR.
We encourage you register your tracking IDs when you confirm a shipment on the Manage Orders page as usual. We’ll notify you once the issue is resolved.
To learn more about VTR requirements, go to Valid Tracking Rate.