I updated my iPhone yesterday and from today I see this red screen wihich says "contact support.apple.com/watch/restore". I followed steps mentioned there:
After performing step 1, it still gives this red screen back. Would you please help me with this?
Apple Watch
If you followed the steps in:
If you see a red "!" on your Apple Watch - Apple Support
Then the third step is:
"If you still need help, contact Apple Support to set up a mail-in repair.":
Make sure you typed it in correctly. Here is how you can look up your Apple Watch model, collection, and color.
Identify your Apple Watch - Apple Support
How to find the serial number or IMEI for your Apple Watch - Apple Support
Yeah, I was thinking to avoid doing mail in order repair.
But if that's the only way, I will try that.
Thank you.
I am trying to place mail in order but,
When I put the serial number of the watch it says, "We’re sorry, but that is not a valid serial number. Please try again."
If your Apple Watch displays 
after a software update, try these steps:
You have to send in your watch as a mail in repair.
Apple Watch red screen "support.apple.com/watch/restore"
