# E28012 — AMBConversationNotFound

No conversation matches the identifier given.

- **HTTP status**: `404`
- **Type**: `not_found_error`
- **Name**: `AMBConversationNotFound`

## What to do

On a send, this means the (from, to) pair names no conversation. Apple issues a customer identifier per brand, so check that from is the business this customer opened a conversation with, and that to is the opaque_user_id from that conversation rather than one from another brand. Your business cannot open a conversation, so a customer who has never messaged you has no identifier to send to. Elsewhere it means no conversation matches the id given.

## Related

- [Regions](/docs/api/regions): matching keys, hosts, and data location
- [E28xxx — Apple Messages for Business](/docs/api/errors/E28xxx): every code in this range
- [Errors](/docs/api/errors): the full wire contract, status mapping, and error catalog
- [Error handling](/docs/guides/errors): branching on `type` and `code`, validation details, and `vendor_code`

## Related resources

- [Should I use a Bird SDK or call the API directly?](/explained/platform/should-i-use-an-sdk-or-call-the-api-directly) (answer)
- [Build your first integration](/learn/paths/integration) (course)
- [Send your first email](/docs/get-started/send-your-first-email) (docs)

[Get an implementation brief](/learn/workspace?topic=api-basics)