<!-- 0Gkit docs — WALLET_CHAIN_MISMATCH
     Source: https://docs.0gkit.com/errors/WALLET_CHAIN_MISMATCH
     LLM-friendly Markdown twin of the page. -->

# WALLET_CHAIN_MISMATCH

**Signer chainId doesn't match active chain**

## What happened

A signer derived for chainId X was asked to sign a transaction for chainId Y. EIP-155 signatures are chain-scoped, so this is a hard error.

## How to fix

Either reconnect the wallet on the target chain (most wallets have a `switchChain` flow) or build a new signer pinned to the target chainId.

## Example

```ts
import { useSwitchChain } from "wagmi";
const { switchChain } = useSwitchChain();
switchChain({ chainId: 16602 }); // Galileo
```

## Reference

- Namespace: `WALLET`
- Help URL: `https://0gkit.com/errors/WALLET_CHAIN_MISMATCH`
- See also: [all error codes](/errors)