Module not found in ngModule imports

I have a strange problem....I use npm install to install ng-push and import PushNotificationsModule from 'ng-push' and place PushNotificationsModule in my ngModule imports. When I do ng build or ng build --prod both builds are success but the dev build fail when of do localhost:3000. The --prod build works. This is the error from chrome:

compiler.js:15989 Uncaught Error: Unexpected value 'PushNotificationsModule' imported by the module 'AppModule'. Please add a @NgModule annotation.
at syntaxError (compiler.js:486)
at compiler.js:15240
at Array.forEach (<anonymous>)
at CompileMetadataResolver.push../node_modules/@angular/compiler/esm5/compiler.js.CompileMetadataResolver.getNgModuleMetadata (compiler.js:15215)
at JitCompiler.push../node_modules/@angular/compiler/esm5/compiler.js.JitCompiler._loadModules (compiler.js:34413)
at JitCompiler.push../node_modules/@angular/compiler/esm5/compiler.js.JitCompiler._compileModuleAndComponents (compiler.js:34374)
at JitCompiler.push../node_modules/@angular/compiler/esm5/compiler.js.JitCompiler.compileModuleAsync (compiler.js:34268)
at CompilerImpl.push../node_modules/@angular/platform-browser-dynamic/esm5/platform-browser-dynamic.js.CompilerImpl.compileModuleAsync (platform-browser-dynamic.js:239)
at PlatformRef.push../node_modules/@angular/core/esm5/core.js.PlatformRef.bootstrapModule (core.js:5578)
at Module../src/main.ts (main.ts:16)


The package.json and appModule are:

package.json:
"ng-push": "0.2.0",
appModule:
import { PushNotificationsModule } from 'ng-push';
@NgModule({
imports: [
BrowserAnimationsModule,
BrowserModule,
........
........
MultipleDatePickerModule,
ChartsModule,
PushNotificationsModule,
.......
]


I am using the following stack:

Angular CLI: 6.2.9
Node: 8.11.4
OS: win32 x64
Angular: 5.2.11
... animations, common, compiler, compiler-cli, core, forms
... http, platform-browser, platform-browser-dynamic
... platform-server, router

Package Version
-----------------------------------------------------------
@angular-devkit/architect 0.8.9
@angular-devkit/build-angular 0.8.9
@angular-devkit/build-optimizer 0.8.9
@angular-devkit/build-webpack 0.8.9
@angular-devkit/core 0.8.9
@angular-devkit/schematics 0.8.9
@angular/cdk 5.2.5
@angular/cli 6.2.9
@angular/material 5.2.5
@ngtools/webpack 6.2.9
@schematics/angular 0.8.9
@schematics/update 0.8.9
rxjs 5.5.12
typescript 2.5.3
webpack 4.16.4


I also noticed that the sequence of my import statements are re-arranged after a build...I never saw this happen before.

Does anyone have an idea whats going on here? any help is appreciated.

EDIT: This is from the GitHub page as to the usage:

Import the PushNotificationsModule in to your AppModule

@NgModule({
imports: [PushNotificationsModule],
declarations: [AppComponent],
bootstrap: [AppComponent]
})
export class AppModule { }

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