On every INR message we get I include a screen shot of the USPS website Tracking.
If ever an A-to-Z I notice they all say "The customer reported an issue with delivery. In this case, the tracking information indicates delivered, but the customer did not receive the package. Because you provided sufficient information that proves order was actually received by the customer, we will not count the claim against your Order Defect "
Example…
Just an FYI