In package.json i have npm start command like:

"start": "node app/src/Server.js",

when i am using "npm start" command then it thrown error of permission denied to open .pem file (ssl file)

Error: EACCES: permission denied, open '/etc/letsencrypt/live/domainname/privkey.pem'

But if i use direct command node app/src/Server.js then it is working. How i can resolve permission issue with npm start? I am using root user only.