chaining operator throwing error in express app

I am trying to use the optional chaining operator (?.) in my express app - it throws SyntaxError whenever I try.

if (user.address?.postal_code.length > 0 ) {                   ^    SyntaxError: Unexpected token '.'      at wrapSafe (internal/modules/cjs/loader.js:1053:16)  

I have tried all variations:

user?.address?.postal_code?.length  user?.address?.postal_code.length  user?.address.postal_code.length    "engines": {          "node": "10.16.0",          "npm": "6.9.0"      },  "dependencies": {          "body-parser": "^1.19.0",          "express": "^4.17.1",          ...      }  

https://stackoverflow.com/questions/66676578/chaining-operator-throwing-error-in-express-app March 17, 2021 at 11:50PM