> For clean Markdown of any page, append .md to the page URL.
> For a complete documentation index, see https://docs.0x.org/llms.txt.
> For AI client integration (Claude Code, Cursor, etc.), connect to the MCP server at https://docs.0x.org/_mcp/server.

# Troubleshooting

> Common issues, error types, and debugging tips for the 0x Solana Swap API.

When working with Solana transactions and the 0x Swap API, you may encounter some common issues. Below are tips to help diagnose and resolve them:

| Issue                                          | Possible Cause                                                      | Suggested Fix                                                                                        |
| ---------------------------------------------- | ------------------------------------------------------------------- | ---------------------------------------------------------------------------------------------------- |
| Transaction fails or gets dropped              | Insufficient SOL for fees, expired blockhash, or network congestion | Ensure your wallet has enough SOL, fetch a fresh blockhash before sending, and retry the transaction |
| Signature verification errors                  | Wrong signer, unsigned transaction, or corrupted transaction data   | Verify the transaction is signed by the correct keypair and that instructions are built correctly    |
| RPC timeout or errors during `sendTransaction` | Network issues or overloaded RPC node                               | Try switching to a different RPC endpoint or increase `maxRetries` in transaction sending options    |
| Unexpected API errors or bad responses         | Incorrect API key or malformed request payload                      | Double-check API keys, endpoint URLs, and request parameters                                         |

#### Debugging Tips

* Log your transaction signature and monitor it on a Solana explorer (e.g. [Solscan](https://solscan.io/)) to track status.
* Use `connection.getLatestBlockhash()` before each transaction to ensure blockhash freshness.
* Use the [transaction confirmation](../get-started.md#transaction-confirmation) step to catch failures early.
* Enable `skipPreflight: false` during development to validate transactions before sending.
* Check API response error messages carefully; they often indicate what went wrong.

If you continue to experience issues, consider reaching out to the 0x developer support or the Solana developer community for assistance.