getting error `Property 'initializeData' does not exist on type of AppConfig` on `useFactory` - angular7

Question

I am fetching data from service on APP_INITIALIZER, but getting error as
Property 'initializeData' does not exist on type of AppConfig
don't know what is the exact issue here. any one help me?
here is my module file:
import { AppConfig } from "./shared-components/auth/AdalService";
import { AppComponent } from './app.component';
import { RoutesModule } from './routes/routes.module';
import { SignInComponent } from './shared-components/user/sign-in/sign-in.component';
export function initializeApp() {
return () => AppConfig.initializeData(); //getting error here
}
#NgModule({
declarations: [
AppComponent,
SignInComponent
],
imports: [
BrowserModule,
AngularFontAwesomeModule,
MsAdalAngular6Module,
TranslateModule.forRoot({
loader: {
provide: TranslateLoader,
useFactory: (createTranslateLoader),
deps: [HttpClient]
},
isolate: true
}),
SharedModule,
HttpClientModule,
iboCalendarModule,
RoutesModule,
// HttpClientInMemoryWebApiModule.forRoot(EventData),
StoreModule.forRoot({}),
EffectsModule.forRoot([]),
StoreDevtoolsModule.instrument({
name:'IBO App',
maxAge:25
})
],
providers: [
{
provide: APP_INITIALIZER,
useFactory: initializeApp,
multi: true,
deps: [AppConfig, SignInComponent ]
},
MsAdalAngular6Service,
{
provide: 'adalConfig',
useFactory: getAdalConfig,
deps: []
},
{
provide: HTTP_INTERCEPTORS,
useClass: InsertAuthTokenInterceptor,
multi: true
}
],
bootstrap: [AppComponent]
})
export class AppModule { }
Here is my service.ts:
import { Injectable, OnInit } from '#angular/core';
import { ShareOption } from "./../user/sign-in/sign-in.component";
import { Store, select } from '#ngrx/store';
import { StateShared } from "./../models/models";
#Injectable({
providedIn: 'root'
})
export class AppConfig {
constructor(){}
initializeData() {
return new Promise((resolve, reject) => resolve(true));
}
}

Answer 1

I bought the service in parameter, got issue fixed. my updated chunk is:
export function initializeApp(service:AppConfig) { //getting service object in param
return () => service.initializeData();
}