The Kaleyra Messaging Platform will return a delivery report (intermediate and/or final, depending on the route) for a specific message to the client application when the registered_delivery field, while submitting the message, is set to 1. In order to retrieve the delivery report from our server
the client will have to connect to the Kaleyra Messaging Platform in the receiver or transceiver mode.
The various status messages pertaining to message delivery and their descriptions are tabulated below:
Message delivered to handset
Message could not be delivered
Message validity period expired; before any valid trials of submission.
Unable to deliver message