Interface's inheritance - Extend an interface in Kotlin

I've started to convert a project's codes from java to Kotlin. I need to extend my BaseAppComponent interface. I've a problem about interface's inheritance. They are in same package.

But I see an error in AppComponent interface.

"Error:(13, 26) Unresolved reference: BaseAppComponent"

I shared my codes... Where is my problem? I couldn't find any example about interface's inheritance on Kotlin.

open interface BaseAppComponent {

    fun inject(defaultApplication: DefaultApplication)
    fun inject(activity: BaseActivity)

    fun plus(comicListModule: ComicListModule): ComicListSubComponent
    fun plus(comicDetailModule: ComicDetailModule): ComicDetailSubComponent
}

@Singleton
@Component(modules = arrayOf(AppModule::class, ServiceModule::class))
interface AppComponent : BaseAppComponent {}

UPDATE:

I could fix but I don't have any idea..

I created a new interface in AppBaseComponent file and I implemented that. After I refactored this interface to outside of that file... I couldn't see any differences between old and new interface, but It's working now..