firebase cloud messaging Request contains an invalid argument

Question

I am getting error while sending message using Firebase cloud messaging admin API.

Error message is below

Caused by:

Answer 1

Yet another cause of this is that your message is too large:

Notification messages can contain an optional data payload. Maximum payload for both message types is 4KB, except when sending messages from the Firebase console, which enforces a 1024 character limit.

https://firebase.google.com/docs/cloud-messaging/concept-options