Intermittent 404 error "Requested entity was not found" from Auth0 Guardian server fails to send push notification

[pexa-aappuhamy]

I have FCM configured with SNS to handle sending push notifications but I am receiving this error intermittently in SNS cloudwatch logs could someone from the Guardian team shed some light on what could be causing this issue?
Cheers.

{
    "notification": {
        "messageId": "<MESSAGE_ID>",
        "timestamp": "2024-11-29 03:22:10.276"
    },
    "delivery": {
        "deliveryId": "<DELIVERY_ID>",
        "destination": "<SNS_DESTINATION_ARN>",
        "providerResponse": "{\"code\":\"404\",\"message\":\"Requested entity was not found.\",\"status\":\"NOT_FOUND\",\"details\":[{\"@type\":\"type.googleapis.com/google.firebase.fcm.v1.FcmError\",\"errorCode\":\"UNREGISTERED\"}]}",
        "dwellTimeMs": 50,
        "token": "<FCM_TOKEN>",
        "statusCode": 404
    },
    "status": "FAILURE"
}