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# Fallback exhausted

POST 

Final notification of an SMS fallback chain: the backup SMS also failed, or it could not be generated. After this event the chain is over — no automatic retry follows.

Unlike the four RCS event types, this event is **not** wrapped in the RCS envelope: it is a plain JSON body. When the backup SMS failed, `message_id` is the identifier of the backup SMS and `origin_identifier` points back to the original RCS `message_id`.

Note: while the backup SMS is alive, its regular status events (`SENT` and the SMS error statuses) arrive as **SMS** webhooks (see the SMS API documentation) carrying `origin_identifier` to correlate them with the RCS send.

Reference: https://docs.chatbridge.mx/rcs/webhooks/rcs-fallback-exhausted-webhook

## Request

### Payload

- `message_id` (string, optional) — Identifier of the message that exhausted the chain: the backup SMS when it failed, or the original RCS send when the SMS could not be generated.
- `status` ("FALLBACK_EXHAUSTED", optional)
- `origin_identifier` (string, optional) — `message_id` of the RCS send that originated the fallback. Present when the event refers to the backup SMS.