When an event occurs that prompts a change in the progress of a Transaction, all stored Callback URLs will receive the following POST payload.

Note that the payload event corresponds to a completed task in the Transaction progress object.

**NOTE: the constructed "progress_url" will be deprecated soon. If you are utilizing the progress_url from the callback, please move to construct it on your end moving forward.

  "event": "progress_changed",
  "timestamp": 1619448709, 
  "payload": { 
    "order_id": "cbd2e6ed-9918-4aca-ac19-f7118bba0d4c", 
    "event": "Title Search Requested",
    "description": "A title search for your transaction was requested on January 1st, 2021."