Multiple notifications create a group but not show time past and count of notifications

In android if multiple notifications it create a group but not show time past and count of notifications in group in after app name

I am using oneSignal native plugin to receive notifications.

cli packages: (C:\Users\hp\AppData\Roaming\npm\node_modules)

@ionic/cli-utils  : 1.19.0
ionic (Ionic CLI) : 3.19.0

global packages:

cordova (Cordova CLI) : 8.0.0

local packages:

@ionic/app-scripts : 3.1.11
Cordova Platforms  : android 7.0.0
Ionic Framework    : ionic-angular 3.9.2

System:

Android SDK Tools : 26.1.1
Node              : v9.4.0
npm               : 5.6.0
OS                : Windows 10

Environment Variables:

ANDROID_HOME : F:\android\sdk

Misc:

backend : pro