Does anyone know how to add an Apple Watch (series 2) to your Apple ID for two factor authentication as a trusted device? I can't seem to figure it out, but I've added all of my other devices by signing in to them.
Your help is greatly appreciated.
Apple Watch Series 2, watchOS 3.1.3
From : Two-factor authentication for Apple ID - Apple Support
A trusted device is an iPhone, iPad, iPod touch with iOS 9 and later, or Mac with OS X El Capitan and later that you've already signed in to using two-factor authentication. It’s a device we know is yours and that can be used to verify your identity by displaying a verification code from Apple when you sign in on a different device or browser.
Two factor authentication for Apple Watch
