Apple watch 2
My apple watch in series 2 can not update , i dont know why?
Apple Watch Series 2, 4
Question marked as
Your iPhone model?
iOS version?
watchOS 5 requires iPhone 5s or later with iOS 12 or later, and Apple Watch Series 1 or later.
watchOS 5 isn't compatible with Apple Watch (first generation). Find your Apple Watch model.
Read here on how to update your Watch: Update your Apple Watch - Apple Support