FCM getting MismatchSenderId

Question

I have an application that uses Google FCM for sending push notifications.

When i send a push notification to a group of users, i get a response of MismatchSen

Answer 1

My problem was solved by entering the correct key as shown below.

Copy Server key like this picture

And then copy this code in post man like this picture

and Body is row like this picture

NOTE:

• You must add key= before Server key in header
• Make sure you enter the header keys correctly (Authorization = "key=..." and ContentType = "application/json")
• You have sent the request to the correct address (https://fcm.googleapis.com/fcm/send and Post method)