Apple Watch Series 2 Fault

Hello,

My Apple Watch Series 2 developed a fault whereby the outer rim of the screen developed a continuous crack.

I enquired at the time (over a year ago) and was told I’d have to pay over 200 for repair.

I see now that it was a manufacturer fault and they are offering to repair for free.

I have subsequently bought a new Apple Watch (series 3) but would like to get my last one repaired as it was a fault with the watch. The only issue is I do not have the original packaging and cannot get the IMEI number. It’s also not listed in my current devices as it’s no longer active.

The watch will not turn on after it stopped working following the crack becoming severe.

Can anyone help out?