TypeError: Cannot read properties of null (reading 'sendTransaction') at ContractFactory.<anonymous>

Question

i am getting this error

TypeError: Cannot read properties of null (reading 'sendTransaction')

when i run the following command :

yarn hardhat run scripts/deploy.js --network Sepolia

deploy.js :

const { ethers } = require("hardhat")

async function main() {
    const SimpleStorageFactory = await ethers.getContractFactory(
        "SimpleStorage"
    )
    console.log("Deploying the contract...")
    const SimpleStorage = await SimpleStorageFactory.deploy()
    await SimpleStorage.deployed()
    console.log(`Contract deployed at address: ${SimpleStorage.address}`)
}

main()
    .then(() => process.exit(0))
    .catch((error) => {
        console.error(error)
        process.exit(1)
    })

hardhat.config.js :

require("@nomicfoundation/hardhat-toolbox")
require("dotenv").config()
const SEPOLIA_RPC_URL = process.env.SEPOLIA_RPC_URL
const PRIVATE_KEY = process.env.PRIVATE_KEY
/** @type import('hardhat/config').HardhatUserConfig */
module.exports = {
    defaultNetwork: "hardhat",
    networks: {
        Sepolia: {
            url: SEPOLIA_RPC_URL,
            accounts: PRIVATE_KEY,
            chainId: 11155111,
        },
    },
    solidity: "0.8.18",
}

Answer 1

You should put your accounts inside an array: accounts: [PRIVATE_KEY] and make sure everything in your .env file is correct. If u still getting error try to console.log() your env variables to see your dotenv package is working fine