Updated iphone software, but watch is now locked and unpaired to phone

See the 'How to erase your Apple Watch if you don't have your iPhone' section in:

Unpair and erase your Apple Watch - Apple Support

or see fireyjack's reply to:

i lost my iphone connected to my apple wa… - Apple Community

Refer to this for info on how to reset watch when its locked https://support.apple.com/en-us/HT204567

How to reset your Apple Watch if you forgot your passcode

Put your watch on its charger and keep it there until you complete these steps.

Press and hold the side button until you see Power Off.

Press and hold the Digital Crown until you see Erase all content and settings.

Tap Reset, then tap Reset again to confirm.

Wait for the process to finish, then set up your Apple Watch again. When asked, restore from a backup.

Sorry about the wait for your answer i was answering some other questions and since i am level 1 i got hit with the posting limits exceeding and i had to wait a few minutes