Angular singleton services shared between library and app

I am developing a library with some singleton services that should be used both by the app that imports the library and by components in the library as well. What I've done:

1)Create a CoreServicesModule with the forRoot method. In the example the method takes an environment parameter which is used in some of these services.

export class CoreServicesModule {
    constructor(@Optional() @SkipSelf() parentModule?: CoreServicesModule) {
        if (parentModule) {
            throw new Error('CoreServicesModule is already loaded. Import it in the AppModule only');
        }
    }

    public static forRoot(environment: any): ModuleWithProviders<CoreServicesModule> {
        return {
            ngModule: CoreServicesModule,
            providers: [
                BaseSingletonService,
                BaseSingletonService2,
                {
                    provide: 'environment',
                    useValue: environment
                }
            ]
        };
    }
}

2)In the application I've injected the service in the component's constructor. I have NOT included the CoreServicesModule in my LibraryComponentModule, where this component is declared.

import { BaseSingletonService } from "@myorg/library/src/library/services";
@Component({
  selector: "library-component",
  templateUrl: "./library-component.component.html",
  styleUrls: ["./library-component.component.scss"],
})
export class LibraryComponent {
  constructor(private baseSingletonService: BaseSingletonService) {}
}

3)Imported the CoreServicesModule inside the application's app.module.ts

@NgModule({
    imports: [
      //...
    CoreServicesModule.forRoot(environment)
  ],
  providers: [],
  declarations: [
  ],
  bootstrap: [AppComponent]
})
export class AppModule {}

Inside the application everything is working as expected. However when I use the library-component I get the NullInjectorError: No provider for BaseSingletonService error. What am I missing? How do you share singleton services between angular library and application?