Invalid Topic Value Provided - While Sending Fcm To A Topic

I am trying to send an FCM message to a topic. But getting 'Invalid topic value provided' error from the server. Json Payload { 'message':{ 'topic':'/topics/news',

Solution 1:

according to doc yor request should be like this:

https://fcm.googleapis.com/fcm/send
Content-Type:application/json
Authorization:key=AIzaSyZ-1u...0GBYzPu7Udno5aA
{
  "to": "/topics/foo-bar",
  "data": {
    "message": "This is a Firebase Cloud Messaging Topic Message!",
   }
}