Registered Alert Endpoint not recieving notifications suddenly

I have a registered alert endpoint and it suddenly stopped working. It is currently set to https://us-central1-lfc-firebase.cloudfunctions.net/postFlightAwareNotifications. All of my other flight aware requests seem to be working, but checking my logs, the endpoint is never even being accessed. Thoughts?

I can confirm the endpoint is working, because I am able to manually send requests to it through Postman.

and I do have an active alert set at:

{
    "GetAlertsResult": {
        "num_alerts": 1,
        "alerts": [
            {
                "alert_id": 28894233,
                "enabled": true,
                "description": "Delta 1996 From KATL",
                "type": "Form_Airline",
                "ident": "DAL1996",
                "user_ident": "",
                "aircrafttype": "",
                "origin": "KATL",
                "destination": "",
                "date_start": 1551571200,
                "date_end": 1551571200,
                "channels": [
                    {
                        "channel_id": 16,
                        "channel_name": "FlightXML push",
                        "mask_summary": "meetingFlight",
                        "e_filed": true,
                        "e_departure": true,
                        "e_arrival": true,
                        "e_diverted": true,
                        "e_cancelled": true,
                        "target_address": "LakeFrontCargo"
                    }
                ],
                "alert_created": 1551582177,
                "alert_changed": 1551582177
            }
        ]
    }
}

Push alerts sent to the listed endpoint are resulting in an HTTP 200 response and the body message “Error: could not handle the request”. Additionally the response time is often greater than two seconds. This indicates an internal exception or timeout may be occurring at the endpoint.

The Push Notification Tester may be helpful for testing. This will allow you to send test alerts on demand with the delivery timestamp visible on the testing interface. This should make it easier to locate any exceptions in the endpoint’s logs.