Hi Tim - try these steps:
On your iPhone, in the Contacts app: check that your contact card contains your name, Apple ID email address and phone number. Remove anyone else's information that may appear there (other than as a Related Name).
On your iPhone: go to Settings > Mail, Contacts, Calendars > in the Contacts section, check that My Info is using your contact card.
On your iPhone: go to Settings > General > Siri > My Info - check that your contact card is selected.
On your iPhone, in the Watch app: go to My Watch > General > About > Name - check and, if required, edit the name of your watch.
On your watch or iPhone: ask Siri "what is my name?"
After making any corrections as required, on your iPhone, in the Watch app:
- Go to: My Watch > General > Reset > tap on Reset Sync Data.
- Nothing will seem to happen, but the process will run in the background / invisibly to the user, so allow a minute or so.
It may then also help to restart both your iPhone and your watch. Turn both devices off first, then restart your iPhone before restarting your watch:
- To turn your watch off: press and hold the side button until you see the Power Off slider; drag the slider to turn off.
- To turn it back on: press and hold the side button until you see the Apple logo.