I cant wake my phone with "Ok Google" anymore I did a factory reset this week of my phone, and now I cannot seem to be able to "wake" my phone saying "Ok Google".

I can use it in the lock screen and everywhere else, but when the screen is off, it will not work anymore. It will remain with the screen off.

Maybe useful information:


I am using a OnePlus 2
I am using "Nova Launcher"


UPDATE

I know that it works, if the phone is being charged. But I would like to have it working, even if the device is NOT charging.
This problem occurs in most android devices. When screen off, OK Google is not working. If you want to use OK Google when screen off, make sure your device is in charging. It will work definitely. Try it in your device.

Recently updated my Pixel to android 8.0 Oreo OS. In android Oreo devices OK Google is working perfectly when screen off.