Announcement reposted from Amazon Japan:
We’ve resolved the tracking ID issue for seller-fulfilled orders that impacted Valid Tracking Rate (VTR) calculation.
We’ve removed temporary measures to prevent listing deactivation due to low VTR, and standard VTR policy will now apply. If your VTR falls below 95% for a product category, your seller-fulfilled offers in that category may be deactivated.
We use a combination of automated means and expert human review to identify VTR issues before any listings are deactivated.
To learn more about VTR policy, go to Valid Tracking Rate.