To stop this night light silently, just say “alexa stop”. Don’t say “stop night light” or “alexa turn off the light” or anything like that. If she still talks when you just say “alexa stop” (or when you start it), then you have the wrong Night Light skill enabled. See above.
https://www.amazon.com/labworks-io-ltd-Night-Light/dp/B0764GDTVG

