Doze mode wont run

[cliqck23]

Hi, can anyone explain how Doze mode works?

I am using GSM Battery Monitor to check my Note5 Doze status, constantly held awake by unknown service/ apps.

Is it because of some chatting apps like Whatsapp/ Line?
Will a device wake up from Doze because of receiving messages/ notifications from messaging apps?

Thanks in advance.

 

[Almeuit]

Here is good information on Doze .

Inside Marshmallow: What is Doze, how do I use it and what does it do? | Android Central