Unauthorized (Error 401) Postman

I am trying to send Push Notifications (using Firebase platform) to my Android app through PostMan Chrome App, but I fail to make it work. I have followed all the instructions on c

Solution 1:

The key specified in the authorization header must be the Server key or Legacy Server key shown in the Firebase console tab for Project Settings > Cloud Messaging. The Web API key shown on the Project Settings > General tab will not work.

Also, the property for the notification text is body, not text:

{
  "to": 
    "/topics/NEWS"
  ,
  "data": {
    "extra_information": "This is some extra information"
  },
  "notification": {
    "title": "NEW NOTIFICATION!",
    "body": "Click me to open an Activity!", // <= CHANGED
    "click_action": "SOMEACTIVITY"
  }
}