Mailgun delivery-status 602 - too old

Question

2 days ago I started to receive a new status code 602 from mailgun when retrieving events from its API

The returned response has

 "delivery-status": {
        "attempt-no": 8,
        "message": "Too old",
        "code": 602,
        "description": "",
        "session-seconds": 0
    }

What does "Too old" exactly mean here? I cant find any documentation on the error codes.

Answer 1

Been going around with Mailgun support on this very issue.

602 is an internal error code that they generate when a message can not be delivered to the recipient. The error is generated after they have attempted to send the messsage for eight hours.