Voice Notifications on iPhone

@user52241 do you have an Apple Watch?
If yes, then by default you would only receive notifications on your Watch when your iPhone screen is locked.

What you could do is turning off the notifications mirroring for the Ring app in your Apple Watch settings.
Once I’ve done it my iPhone started ringing and showing Ring notifications with the screen locked, with no notifications triggered on my Apple Watch anymore - which IMHO are useless anyway since you can’t really take actions from your Watch other than acknowledging the notifications.