---
title: numbers.busy
description: The number was changed by someone else at the same moment; retry.
summary: >-
  Returned with 503 and Retry-After when a number claim or trial conversion lost
  a race with another change to the same number on every attempt. Nothing is
  debited.
date: 2026-10-10T00:00:00.000Z
type: error
---


## Summary

`numbers.busy` is returned by `POST /v1/numbers/{id}/claim` (and by the Desk onboarding number endpoints) when the claim lost a race with another change to the same number, such as a price change or another claim, on every bounded attempt. Nothing was debited.

## Cause

Two changes to one number happened at the same moment. The platform retries the whole claim a few times before giving up.

## Resolution

Wait the number of seconds in the `Retry-After` header (one second) and send the same request again. Use the same `Idempotency-Key`: a retried claim never debits twice.

## Example response

```json
{
  "error": {
    "code": "numbers.busy",
    "message": "this number was changed by someone else at the same moment; retry in a second",
    "request_id": "req_01900000abc"
  }
}
```

## Next steps

- See [Numbers API](/developers/api#numbers) for number search and claim.