Hi
The following steps may help, having previously resolved the same issue for other users:
If you have not yet done so, update your iPhone and Apple Watch to the latest software, starting with your iPhone:
- Update the iOS software on your iPhone, iPad, or iPod touch - Apple Support
- Update the software on your Apple Watch - Apple Support
On your iPhone, go to: Settings > General > Reset - tap once on Reset Keyboard Dictionary.
Restart your iPhone (normally):
Unpair and re-pair your Apple Watch:
The Watch app on your iPhone takes a backup of your watch automatically when unpairing via the app.
Initially choose to Restore from Backup during set up (most data and settings will be restored, with some exceptions, such as Apple Pay cards, passcode).
If the issue persists, try unpairing and setting up as a new watch.
- Unpair your Apple Watch and iPhone - Apple Support
- Set up your Apple Watch - Apple Support