How to add buttons in ionic FCM push notification

Ionic Framework
1

Hello
I would like to send a push notification with 2 buttons: subscribe and unsubscribe.
I am receiving the notification, but it does not have the buttons.
here is the code of the notification:

let notification = {
      "notification": {
        "title": title,
        "body": msg,
        "sound": "default",
        "click_action": "FCM_PLUGIN_ACTIVITY",
      }, 
      "actions": [
          {
            "title": "Subscribe",
            "action": "subscribe",
          },
          {
            "title": "Unsubscribe",
            "action": "unsubscribe"
          }
        ]
      ,
        "android":{
        "ttl":"2419200s"
      },
      "to":'/topics/'+topic,
      "priority": "high"
    };

Help me please

2

@rapropos please can you help me?