google cloud messaging - Android notifications not work when sent through Amazon SNS -

we have been sending messages through amazon sns , google cloud messaging (gcm) android device. raw sns json message entering sns send message function:

{     "gcm": "{\"data\":{\"somedata\":62},\"notification\":{\"body\":\"body message\",\"title\":\"a title\"}}",     "default": "my default message" } 

for reason notification section it's title , body appear ignored. no notification appearing on device.

can confirm notifications can sent through sns or there (as suspect) limitation data{...} part of json understood?