In order for Noonlight to share your accurate location with someone in your Safety Network, your phone needs to be turned on and you need to set your location settings for the app to Allow Location Access: Always and turn ON Precise Location. You can read how to do that here.
Safety Network is currently only available on iOS. If you have an Android device, you can still be invited to other people’s Safety Networks, but you won’t be able to create your own network and other people won’t be able to track your location, even if you have the Noonlight app.