getting device serial number

My company is deploying remote devices to locations. We are managing these devices in JAMF and I need a way to register them to the location.
Last year I used Expo to create an app that did this with the device serial number.
I am making another app right now that is going to use some API functions in JAMF. The places our devices are being sent to are people we cannot rely upon getting the serial.
I need a way for Expo to get the serial number so our API can register the device in JAMF. However, I do not see anything anymore that shows this, i have looked in device-info and constants.
Where did it go?