Error when run npm start

[Denisphuket]

Hi! i have this problem:

root@sova-games:/var/www/html/whatsapp-web-reveng# npm start

> whatsapp-web-reveng@1.0.0 start /var/www/html/whatsapp-web-reveng
> npm run dev

> whatsapp-web-reveng@1.0.0 dev /var/www/html/whatsapp-web-reveng
> concurrently --kill-others "./node_modules/.bin/nodemon index.js -i client -e js" "./node_modules/.bin/nodemon --ex
ec python ./backend/whatsapp_web_backend.py -i client -e py" "sass --watch client/css/main.scss:client/css/main.css"

sh: 1: concurrently: not found
npm ERR! file sh
npm ERR! code ELIFECYCLE
npm ERR! errno ENOENT

npm ERR! syscall spawn
npm ERR! whatsapp-web-reveng@1.0.0 dev: `concurrently --kill-others "./node_modules/.bin/nodemon index.js -i client -
e js" "./node_modules/.bin/nodemon --exec python ./backend/whatsapp_web_backend.py -i client -e py" "sass --watch cli
ent/css/main.scss:client/css/main.css"`
npm ERR! spawn ENOENT
npm ERR!
npm ERR! Failed at the whatsapp-web-reveng@1.0.0 dev 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!     /root/.npm/_logs/2019-04-01T11_55_46_214Z-debug.log
npm ERR! code ELIFECYCLE
npm ERR! errno 1
npm ERR! whatsapp-web-reveng@1.0.0 start: `npm run dev`
npm ERR! Exit status 1
npm ERR!
npm ERR! Failed at the whatsapp-web-reveng@1.0.0 start 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!     /root/.npm/_logs/2019-04-01T11_55_46_230Z-debug.log`

log file:
`0 info it worked if it ends with ok
1 verbose cli [ '/root/.nvm/versions/node/v11.13.0/bin/node',
1 verbose cli   '/root/.nvm/versions/node/v11.13.0/bin/npm',
1 verbose cli   'run',
1 verbose cli   'dev' ]
2 info using npm@6.7.0
3 info using node@v11.13.0
4 verbose run-script [ 'predev', 'dev', 'postdev' ]
5 info lifecycle whatsapp-web-reveng@1.0.0~predev: whatsapp-web-reveng@1.0.0
6 info lifecycle whatsapp-web-reveng@1.0.0~dev: whatsapp-web-reveng@1.0.0
7 verbose lifecycle whatsapp-web-reveng@1.0.0~dev: unsafe-perm in lifecycle true
8 verbose lifecycle whatsapp-web-reveng@1.0.0~dev: PATH: /root/.nvm/versions/node/v11.13.0/lib/node_modules/npm/node_modules/npm-lifecycle/node-gyp-bin:/var/www/html/whatsapp-web-reveng/node_modules/.bin:/root/.nvm/versions/node/v11.13.0/lib/node_modules/npm/node_modules/npm-lifecycle/node-gyp-bin:/var/www/html/whatsapp-web-reveng/node_modules/.bin:/root/.nvm/versions/node/v11.13.0/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/snap/bin
9 verbose lifecycle whatsapp-web-reveng@1.0.0~dev: CWD: /var/www/html/whatsapp-web-reveng
10 silly lifecycle whatsapp-web-reveng@1.0.0~dev: Args: [ '-c',
10 silly lifecycle   'concurrently --kill-others "./node_modules/.bin/nodemon index.js -i client -e js" "./node_modules/.bin/nodemon --exec python ./backend/whatsapp_web_backend.py -i client -e py" "sass --watch client/css/main.scss:client/css/main.css"' ]
11 info lifecycle whatsapp-web-reveng@1.0.0~dev: Failed to exec dev script
12 verbose stack Error: whatsapp-web-reveng@1.0.0 dev: `concurrently --kill-others "./node_modules/.bin/nodemon index.js -i client -e js" "./node_modules/.bin/nodemon --exec python ./backend/whatsapp_web_backend.py -i client -e py" "sass --watch client/css/main.scss:client/css/main.css"`
12 verbose stack spawn ENOENT
12 verbose stack     at ChildProcess.<anonymous> (/root/.nvm/versions/node/v11.13.0/lib/node_modules/npm/node_modules/npm-lifecycle/lib/spawn.js:48:18)
12 verbose stack     at ChildProcess.emit (events.js:193:13)
12 verbose stack     at maybeClose (internal/child_process.js:1001:16)
12 verbose stack     at Process.ChildProcess._handle.onexit (internal/child_process.js:266:5)
13 verbose pkgid whatsapp-web-reveng@1.0.0
14 verbose cwd /var/www/html/whatsapp-web-reveng
15 verbose Linux 2.6.32-042stab136.1
16 verbose argv "/root/.nvm/versions/node/v11.13.0/bin/node" "/root/.nvm/versions/node/v11.13.0/bin/npm" "run" "dev"
17 verbose node v11.13.0
18 verbose npm  v6.7.0
19 error file sh
20 error code ELIFECYCLE
21 error errno ENOENT
22 error syscall spawn
23 error whatsapp-web-reveng@1.0.0 dev: `concurrently --kill-others "./node_modules/.bin/nodemon index.js -i client -e js" "./node_modules/.bin/nodemon --exec python ./backend/whatsapp_web_backend.py -i client -e py" "sass --watch client/css/main.scss:client/css/main.css"`
23 error spawn ENOENT
24 error Failed at the whatsapp-web-reveng@1.0.0 dev script.
24 error This is probably not a problem with npm. There is likely additional logging output above.
25 verbose exit [ 1, true ]

[sigalor]

You probably did not run npm install before trying to run the application.

If you did, changing concurrently to npx concurrently in package.json might help.