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

# E1747 — CIP-34: auction grant nonce already used

> CIP-34: auction grant nonce already used

# E1747 — CIP-34: auction grant nonce already used

| Property | Value |
| - | - |
| **Code** | `1747` |
| **Slug** | `E1747` |
| **Category** | `commit_reveal` (Commit-Reveal) |
| **CIP** | CIP-34 §Sealed-Bid |

## What happened

Cip34: auction grant nonce already used.

This is the receipt's `what` text, produced by the node's `ExecutionError::AuctionGrantNonceUsed`.

## Why it happened

The node rejected the operation with `E1747` (category `commit_reveal`, Commit-Reveal). The receipt's `why` field carries the specific cause and `context` carries structured details, when the emitter attaches any.

The normative rule is in CIP-34 §Sealed-Bid.

## How to fix

This (originator, nonce) pair already opened an auction; have the originator sign a new grant with an unused nonce.

## Receipt example

```json theme={null}
{
  "code": 1747,
  "slug": "E1747",
  "category": "commit_reveal",
  "what": "cip34: auction grant nonce already used",
  "fix": "This (originator, nonce) pair already opened an auction; have the originator sign a new grant with an unused nonce.",
  "docs_url": "https://docs.cowboy.inc/errors/E1747"
}
```

***

> [card] [All Error Codes](https://docs.cowboy.inc/errors/overview.md)
>
> View the complete error code reference


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