My Apple Watch was stole I have the iMessage number
My Apple Watch was stole I have the iMei
Apple Watch Series 6, watchOS 8
Question marked as
Report your lost or stolen device to local law enforcement. Law enforcement might request the serial number of your device. Find your device serial number.
Find My is the only way that you can track or locate a lost or missing device. If Find My isn't enabled on your watch before it goes missing, there is no other Apple service that can find, track, or otherwise flag your device for you.
Follow all instructions here: If Find My iPhone or Find My iPad isn't enabled on your missing device - Apple Support
For more info: If your Apple Watch is lost or stolen