# E21048 — VoiceInboundNumberAlreadyClaimed

Another SIP trunk already answers this inbound number.

- **HTTP status**: `409`
- **Type**: `conflict_error`
- **Name**: `VoiceInboundNumberAlreadyClaimed`

## What to do

Remove the number from the trunk that currently answers it, then add it here. One number can be answered by one trunk.

## Related

- [Idempotency](/docs/api/idempotency): safe retries and key reuse rules
- [E21xxx — Voice & SIP trunking](/docs/api/errors/E21xxx): 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`