# last-audited-event-mismatched

The event that **`lastAuditedEvent`** names has **another hash** in the database.

- **Route:** `audit-history`
- **Description:** `last audited event is mismatched: the event with its ID has another hash, so the events changed since the previous audit, or the anchor does not come unchanged from this database`
- **Details:** **`value`**, the hash of `lastAuditedEvent` as the request gave it.

## Why It Happens

An **[audit](/docs/eventsourcingdb/auditing-the-event-store)** checks the chain of events from the first one on, and at the event with the ID of `lastAuditedEvent`, it compares the hash of that event with the one the request gives. The chain up to there is intact, since a broken chain is reported first, as **[`event-chain-broken`](/docs/eventsourcingdb/errors/event-chain-broken)**, but it **is not the chain the previous audit saw**: since every hash covers the one before it, at least one event up to that one differs from what the previous audit read.

That is the case when the events were replaced together with their hashes, but also when the anchor does not come unchanged from this database: when it comes from **another database**, when the database was **restored from another backup** since the previous audit, or when the anchor was not kept as the previous audit answered it, such as a hash of version 2 without its prefix `esdb:hash:v2:`.

## How to Fix It

Check that the anchor is the one the previous audit of this database answered. If it is, **the events have changed since that audit**, which calls for an investigation rather than another request: sending the same request again fails the same way.

## Example

For an audit anchored at the event `41`, with a hash that this event does not have in the database, EventSourcingDB answers with this error, as a line of the stream, and then ends the stream with its `end` item:

```json
{
  "type": "error",
  "data": {
    "code": "https://docs.eventsourcingdb.io/errors/last-audited-event-mismatched",
    "description": "last audited event is mismatched: the event with its ID has another hash, so the events changed since the previous audit, or the anchor does not come unchanged from this database",
    "details": {
      "value": "esdb:hash:v2:31483ec2de3d027913dcb424efb1b80b59994bf2e6ba7f3a2a6b00a192f4979f"
    }
  }
}
```