I am trying to build a frontend with NextJS/React/Web3js and I'm running into one of my last hurdles. Any functions I call to my contract that requires signing doesn't work.

I suspect it's because I have two web3 objects, one initialized via Metamask and another using an Infura RPC.

Initially I had a file to initialize the Contract object in:

import Web3 from "web3"
import buildData from '../../build/contracts/Contract.json'

const provider = new Web3.providers.HttpProvider(
const web3 = new Web3(provider)

const bContract = new web3.eth.Contract(buildData.abi,"0x6841121b8CC025D2558eBC1a7144B17B1F25159B")

export default bContract

And in my main file I had the function that initialized another web3 object with Meta mask here,

    const connectWalletHandler = async () => {
        // Check if Metamask is available
        if (typeof window !== "undefined" && typeof window.ethereum !== "undefined") {
            try {
                //request wallet connect
                await window.ethereum.request({ method: "eth_requestAccounts" })

                //set web3 instance
                web3 = new Web3(window.ethereum)

                //get list of accounts
                const accounts = await web3.eth.getAccounts()

            } catch (err) {
        } else {
            // meta not installed
            console.log("Please install Metamask")

But when I call functions to send transactions, I get a "method is not defined" error.


try {
             await contract.methods.placeBet(id).send({
                from: account,
                value: web3.utils.toWei(userBet,'ether')
        } catch (err) {

Returned error: The method eth_sendTransaction does not exist/is not available

Yet if I use a call function to read some variable on the contract, it works swimmingly. What am I doing wrong?

1 Answer 1


I figured out the issue. It was indeed having 2 web3 objects created, one with Metamask, the other through the Web3 package. I couldn't sign transactions with the latter as expected as I didn't have the private key. So I ended up passing the web3 object created by Metamask to create the local Contract object in the first code block I had above.

Thank you lads for reading this, just writing out your thoughts is quite helpful for debugging.

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