Error('username is required').error occur by using twilio - node.js

Question

i tried all the methods to resolve this problem but i couldn't resolved it it shows the error using twilio to generate otp and verify it.Error: username is required this error will shows i will install dotenv and all the npm packages
index.js
const express = require("express")
const app = express()
const port=4000
app.listen(port,()=>{
console.log(`Server is running at ${port}`)
})
const config=require('./config');
const client = require('twilio')(process.env.ACCOUNT_SID, process.env.AUTH_TOKEN)
// /login
// - phone number
// - channel (sms/call)
// /verify
// - phone number
// - code
app.get('/', (req, res) => {
res.status(200).send({
message: "You are on Homepage",
info: {
login: "Send verification code through /login . It contains two params i.e. phonenumber and channel(sms/call)",
verify: "Verify the recieved code through /verify . It contains two params i.e. phonenumber and code"
}
})
})
// Login Endpoint
app.get('/login', (req, res) => {
if (req.query.phonenumber) {
client
.verify
.services(process.env.SERVICE_ID)
.verifications
.create({
to: `+${req.query.phonenumber}`,
channel: req.query.channel === 'call' ? 'call' : 'sms'
})
.then(data => {
res.status(200).send({
message: "Verification is sent!!",
phonenumber: req.query.phonenumber,
data
})
})
} else {
res.status(400).send({
message: "Wrong phone number :(",
phonenumber: req.query.phonenumber,
data
})
}
})
// Verify Endpoint
app.get('/verify', (req, res) => {
if (req.query.phonenumber && (req.query.code).length === 4) {
client
.verify
.services(process.env.SERVICE_ID)
.verificationChecks
.create({
to: `+${req.query.phonenumber}`,
code: req.query.code
})
.then(data => {
if (data.status === "approved") {
res.status(200).send({
message: "User is Verified!!",
data
})
}
})
} else {
res.status(400).send({
message: "Wrong phone number or code :(",
phonenumber: req.query.phonenumber,
data
})
}
})
// listen to the server at 3000 port
app.listen(port, () => {
console.log(`Server is running at ${port}`)
})
const client and all the const variables or all the process i will shows but error occurs and i don't know the exact solution.
config.js
username is required error occurs i tried all the possibilities that i saw so kindly help me please