Why my mern app cannot be deployed to Heroku? - node.js

Question

Im trying to deploy my MERN stack app to Heroku, I have done the necessary configuration on my package.json file, I have tried both Heroku CLI and Github Deploy at Dashboard Heroku but somehow it doesn't deploys... I have heroku postbuild script, which i checked on multiple sites and confirmed
here is my package.json;
{
"name": "devconnector",
"version": "1.0.0",
"description": "Social Network for Developers",
"main": "server.js",
"scripts": {
"start": "node server",
"server": "nodemon server",
"client": "npm start --prefix client",
"dev": "concurrently \"npm run server\" \"npm run client\"",
"heroku-postbuild": "NPM_CONFIG_PRODUCTION=false npm install --prefix client && npm run build --prefix client"
},
"engines": {
"node": "14.11.0"
},
"keywords": [],
"author": "",
"license": "ISC",
"dependencies": {
"bcryptjs": "^2.4.3",
"config": "^3.3.2",
"express": "^4.17.1",
"express-validator": "^6.6.1",
"gravatar": "^1.8.1",
"jsonwebtoken": "^8.5.1",
"mongoose": "^5.10.7",
"request": "^2.88.2"
},
"devDependencies": {
"concurrently": "^5.3.0",
"nodemon": "^2.0.4"
}
}
here is the error log;
-----> Node.js app detected
-----> Creating runtime environment
NPM_CONFIG_LOGLEVEL=error
NODE_ENV=production
NODE_MODULES_CACHE=true
NODE_VERBOSE=false
-----> Installing binaries
engines.node (package.json): 14.11.0
engines.npm (package.json): unspecified (use default)
Resolving node version 14.11.0...
Downloading and installing node 14.11.0...
Using default npm version: 6.14.8
-----> Installing dependencies
Installing node modules
> nodemon#2.0.4 postinstall /tmp/build_704248b1_/node_modules/nodemon
> node bin/postinstall || exit 0
Love nodemon? You can now support the project via the open collective:
> https://opencollective.com/nodemon/donate
added 324 packages in 7.74s
-----> Build
Running heroku-postbuild
> devconnector#1.0.0 heroku-postbuild /tmp/build_704248b1_
> NPM_CONFIG_PRODUCTION=false npm install --prefix client && npm run build --prefix client
up to date in 0.245s
found 0 vulnerabilities
npm ERR! code ENOENT
npm ERR! syscall open
npm ERR! path /tmp/build_704248b1_/client/package.json
npm ERR! errno -2
npm ERR! enoent ENOENT: no such file or directory, open '/tmp/build_704248b1_/client/package.json'
npm ERR! enoent This is related to npm not being able to find a file.
npm ERR! enoent
npm ERR! A complete log of this run can be found in:
npm ERR! /tmp/npmcache.TlmrF/_logs/2020-10-05T13_06_26_346Z-debug.log
npm ERR! code ELIFECYCLE
npm ERR! errno 254
npm ERR! devconnector#1.0.0 heroku-postbuild: `NPM_CONFIG_PRODUCTION=false npm install --prefix
client && npm run build --prefix client`
npm ERR! Exit status 254
npm ERR!
npm ERR! Failed at the devconnector#1.0.0 heroku-postbuild script.
npm ERR! This is probably not a problem with npm. There is likely additional logging output above.
npm ERR! A complete log of this run can be found in:
npm ERR! /tmp/npmcache.TlmrF/_logs/2020-10-05T13_06_26_372Z-debug.log
-----> Build failed
We're sorry this build is failing! You can troubleshoot common issues here:
https://devcenter.heroku.com/articles/troubleshooting-node-deploys
If you're stuck, please submit a ticket so we can help:
https://help.heroku.com/
Love,
Heroku
! Push rejected, failed to compile Node.js app.
! Push failed