Can't find /ngx at Contacts

Ionic Framework ionic-v3
1

I followed this link on accessing and managing contact and followed the installation of step 1.

When I got to step 2 and tried to put it in the node module it gave an error saying that it can’t find the file

my app.module has import { Contact } from ‘@ionic-native/contacts/ngx’ and my providers has Contact but when I tried to run it without /ngx it says the following

index.js:112 Uncaught TypeError: Object(...) is not a function
    at index.js:112
    at Module../node_modules/@ionic-native/contacts/index.js (index.js:130)
    at __webpack_require__ (bootstrap:83)
    at Module../src/app/app.module.ts (app.component.ts:18)
    at __webpack_require__ (bootstrap:83)
    at Module../src/main.ts (main.ts:1)
    at __webpack_require__ (bootstrap:83)
    at Object.0 (main.ts:12)
    at __webpack_require__ (bootstrap:83)
    at checkDeferredModules (bootstrap:45)
(anonymous) @ index.js:112
./node_modules/@ionic-native/contacts/index.js @ index.js:130
__webpack_require__ @ bootstrap:83
./src/app/app.module.ts @ app.component.ts:18
__webpack_require__ @ bootstrap:83
./src/main.ts @ main.ts:1
__webpack_require__ @ bootstrap:83
0 @ main.ts:12
__webpack_require__ @ bootstrap:83
checkDeferredModules @ bootstrap:45
webpackJsonpCallback @ bootstrap:32
(anonymous) @ main.js:1