> ## Documentation Index
> Fetch the complete documentation index at: https://docs.kash.bot/llms.txt
> Use this file to discover all available pages before exploring further.

# CONFIRMATION_TOKEN_USED

> HTTP 409 — Confirmation token used

**HTTP status:** 409 · **Title:** "Confirmation token used"

## When it fires

The token has already been redeemed. Confirmation tokens are **one-time use** — the first successful confirm clears the stored hash so a replay can't re-fire the trade.

## Why it happens

* A retry layer that doesn't check the trade's status before re-confirming (most common).
* Two parallel confirmation attempts from the same consumer (race condition in the caller).
* A double-click in a human-in-the-loop UI.

## How to fix

* Check the trade's status via `GET /v1/trades/:id` — if it's anything past `pending_confirmation`, the confirm already succeeded.
* Make your retry loop idempotent: poll trade status first, only confirm if `status === 'pending_confirmation'`.
* For UI flows: disable the confirm button immediately on click to prevent double-submission.

## Related codes

* [`TRADE_NOT_AWAITING_CONFIRMATION`](./TRADE_NOT_AWAITING_CONFIRMATION.md) — same outcome via different state-check path