TN Khanh

Thanks. Because I somehow cannot make it work with web3.js but it works with ethers. I will stick with ethers for now.

I got this error when sending the `rawTx` ``` "error":{"code":-32000,"message":"only replay-protected (EIP-155) transactions allowed over RPC"} ``` I look around and find `chainId` might be missing in the transaction (ref....