optns https://w1.nandbox.net/message-ack
This object represents outbound message acknowledgment details.
| Field | Type | Required | Description |
|---|---|---|---|
| reference | Long | Yes | Unique local identifier for the original message. |
| message_id | String | Yes | Global Unique identifier for the original message. |
| date | Long | Yes | Date the message was sent in Unix Epoch timestamp in milliseconds |