This event notifies you of a message that could not be sent using phone number. This happens mostly when there is no Viber account associated with a given phone number.

{
  "event": "message_failed",
  "timestamp" : "2017-12-29T17:26:17.331Z",
  "data" : {
    "channel": {
      "id": "6456078759331238786",
      "type": "viber_business_messages"
    },
    "contact": {
      "id": "6456078781510718339",
      "phone_number": "15558576309"
    },
    "message": {
      "id": "6456078996108088196"
    },
    "error": {
      "code": 3,
      "message": "Cannot find Viber user for given phone number."
    }
  }
}

Parameter	Type	Description
data.channel	object	Channel where the `data.contact` resides in.
data.contact	object	Contact to whom the message was sent but not delivered.
data.message	object	Messages which was sent, will contain only `message.id`.
data.error.code	number	Error code, see errors below.
data.error.message	string	Detail message of an error, see errors below.

Errors

Error Code	Reason
1	Error while processing the request.
2	Sending messages to this user is blocked.
3	Cannot find user for given phone number.
4	Message failed to be delivered within specified time (see channel property `default_message_ttl`).