We are aware of an issue where emails sent to USG.com are bouncing back. After investigating, we’ve found that USG’s email filtering systems are modifying the emails during their security scans, which changes the email’s source address to their system’s IP (148.163.140.163). This is causing the emails to be blocked.
We have reached out to USG and offered to work together on resolving the issue. Since we don’t manage their security systems or have access to their environment, we’re dependent on their team to address this on their end.
We will keep you informed as soon as we have updates. Thank you for your understanding and patience.