Hi crystal03,
We appreciate you using our Apple Support Communities to inquire out about your Apple Watch, and this message you're seeing. We're glad to help sort it out.
As your Watch has been removed from your iPhone and you're unable to get into the Settings app to choose the option to Erase All Content and Settings, you'll want to follow the steps in this guide:
Erase Apple Watch
Specifically, refer to these steps:
"If you can’t access the Settings app on your Apple Watch because you’ve forgotten your passcode, put your Apple Watch on its charger, then press and hold the side button until you see Power Off. Firmly press the Power Off slider, then lift your finger. Tap Erase all content and settings."
Let us know if this helps.
Have a great day!