Can’t find IMEI NUMBER ON Apple Watch Series 2. This watch isn’t currently in use as I replaced with Apple Watch SE

On the watch open the Settings app.

Tap on your name.

Scroll down and tap the name of your watch.

Scroll down to see the IMEI number.

You likely have to pair the watch to your iPhone to do the steps above. You can pair more than one watch to your iPhone.

M1 Mac mini, macOS 12.3; Watch, series 5 GPS/cellular, watchOS 8.5; iPad Pro 2nd Gen, iPadOS 15.4; iPhone 12 Pro, iOS 15.4; TV 4th Gen, tvOS 15.4; HomePods, audioOS 15.4 and Airport Express w/ Airplay 2

I do not think the Series 2 had Cellular. I think Cellular was added in the Series 3

The Apple Watch SE can have cellular (or be a GPS only model for less cost).

Identify your Apple Watch - Apple Support

Looking at the above page, it appears to be a Series 2

i need to find imei on apple watch modle A1758

the watch is not working