There is a voluntary upgrade program for 320’s.
"Note regarding Invalid Serial Message: If your P320 was manufactured after our voluntary upgrade program started (August 8, 2017), it already includes the upgrade by default, which is why our system may not recognize the serial number. For P320s produced before this date, please double-check your serial number to ensure it's entered correctly. If you're still experiencing issues, don't hesitate to contact our customer service team for assistance"
https://www.sigsauer.com/p320-voluntary-upgrade-program
"Note regarding Invalid Serial Message: If your P320 was manufactured after our voluntary upgrade program started (August 8, 2017), it already includes the upgrade by default, which is why our system may not recognize the serial number. For P320s produced before this date, please double-check your serial number to ensure it's entered correctly. If you're still experiencing issues, don't hesitate to contact our customer service team for assistance"
https://www.sigsauer.com/p320-voluntary-upgrade-program