{"success":false,"message":"HTTP Error: 400","response":"{\n  \"error\": {\n    \"code\": 400,\n    \"message\": \"The registration token is not a valid FCM registration token\",\n    \"status\": \"INVALID_ARGUMENT\",\n    \"details\": [\n      {\n        \"@type\": \"type.googleapis.com\/google.firebase.fcm.v1.FcmError\",\n        \"errorCode\": \"INVALID_ARGUMENT\"\n      },\n      {\n        \"@type\": \"type.googleapis.com\/google.rpc.BadRequest\",\n        \"fieldViolations\": [\n          {\n            \"field\": \"message.token\",\n            \"description\": \"The registration token is not a valid FCM registration token\"\n          }\n        ]\n      }\n    ]\n  }\n}\n"}