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

# How-to: Troubleshoot failed transactions

> Diagnose and resolve failed transactions using error details, parameter checks, and the Tenderly debugging tool.

## Overview

* Helps you interpret `errorReason` and `errorDetails` fields returned on failed
  transactions.
* Guides you through systematic checks to identify the root cause of a failure.

## Prerequisites

Before you begin:

* You have a failed transaction with an `errorReason` of `ESTIMATION_ERROR` or
  another error code.
* You have reviewed the error fields in the transaction object. See
  [Transaction states and errors](/wallets/asynchronous-states-and-statuses) for
  a full list of error codes and their meanings.

## Steps

### Step 1. Read the error message

Check the `errorDetails` field carefully. Many errors are self-explanatory, for
example, "Insufficient balance" or "Not authorized." Cross-reference the value
against the
[ESTIMATION\_ERROR details](/wallets/asynchronous-states-and-statuses#estimation_error-details)
tables to identify the category and recommended remedy.

### Step 2. Verify contract addresses

Confirm that you are interacting with the correct contract on the correct
network. A transaction sent to the wrong contract address or the wrong network
will fail or produce unexpected results.

### Step 3. Verify transaction parameters

Ensure all addresses, amounts, and other parameters are correct:

* Recipient addresses are valid and non-zero.
* Token amounts meet or exceed any minimum thresholds.
* ABI signatures match the function being called.

### Step 4. Check token balances and allowances

Many errors stem from insufficient balances or missing approvals:

* Verify the wallet has enough of the token being transferred.
* For ERC-20 interactions involving a spending contract, confirm the wallet has
  called `approve()` to grant sufficient allowance.

### Step 5. Review contract state

Some operations are only valid in certain contract states. Confirm that the
contract is not paused and that any role-based access requirements are
satisfied.

### Step 6. Verify authorization

Ensure the calling wallet has the permissions required by the contract. Check
for role assignments and blocklist status if you are working with regulated
tokens such as USDC.

### Step 7. Retry time-sensitive operations

For errors related to expired signatures, nonces, or network conditions, retry
the operation:

* Generate a fresh signature or nonce if the original has expired.
* Retry after a short delay if the error suggests an RPC node was temporarily
  unavailable.

## Debug with Tenderly

For complex errors where `errorDetails` does not provide enough information, use
[Tenderly](https://tenderly.co/) to simulate and inspect the failing
transaction. Tenderly lets you step through execution and identify exactly where
and why the transaction reverts.