> ## Documentation Index
> Fetch the complete documentation index at: https://signatureapi-daf4ee54.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Invalid API Key

> Error

## What Happened

The API key used to authenticate the request was not recognized.

## How to Fix

* Check that the API key is complete and has not been truncated. API keys start with `key_test_` or `key_live_`, and the prefix is part of the key.
* Ensure the API key is passed in the `X-API-Key` header, not in the `Authorization` header or as a query parameter.
* Verify the key has not been revoked or regenerated in your [Dashboard](https://dashboard.signatureapi.com).
* If you recently created the key, wait a few seconds and try again.

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