Почему не загружается фрагмент при запуске приложения?

Question

[veronika_elizarova]

Пытаюсь сделать Navigation Component + Bottom Navigation View. Не понимаю, почему в main activity при запуске приложения не отображается NavHostFragment. В визуальном редакторе все как положено.
Ниже привожу разметку main activity:

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".presentation.view.MainActivity">

    <com.google.android.material.bottomnavigation.BottomNavigationView
        android:id="@+id/bottom_nav"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:backgroundTint="#FFFFFF"
        app:backgroundTint="@color/purple_500"
        app:itemIconTint="@drawable/bottom_nav_selector"
        app:itemTextColor="@color/black"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:menu="@menu/bottom_menu" />

    <androidx.fragment.app.FragmentContainerView

        android:id="@+id/nav_host_fragment"

        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        android:name="androidx.navigation.fragment.NavHostFragment"
        app:defaultNavHost="true"
        app:navGraph="@navigation/navigator"/>

Код самой активити ( пробовала убрать все из onCreate, не помогло ):

class MainActivity : AppCompatActivity () {
    private lateinit var  binding: ActivityMainBinding
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)
        binding = ActivityMainBinding.inflate(layoutInflater)
        setContentView(binding.root)
 
        val navHostFragment = supportFragmentManager.findFragmentById(R.id.nav_host_fragment) as NavHostFragment
        val navController = navHostFragment.navController
 
        val appBarConfiguration = AppBarConfiguration(setOf(R.id.petFragment2,R.id.tasksFragment2,R.id.settingsFragment2))
        val bottomNavigationView = findViewById<BottomNavigationView>(R.id.bottom_nav)
        setupActionBarWithNavController(navController, appBarConfiguration)
        bottomNavigationView.setupWithNavController(navController)


    }
}

А вот и сам navigation:

<?xml version="1.0" encoding="utf-8"?>
<navigation xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/navigator"
    app:startDestination="@id/petFragment2">
    <fragment
        android:id="@+id/settingsFragment2"
        android:name="com.android.petdiary.presentation.view.SettingsFragment"
        android:label="fragment_settings"
        tools:layout="@layout/fragment_settings" />
    <fragment
        android:id="@+id/tasksFragment2"
        android:name="com.android.petdiary.presentation.view.TasksFragment"
        android:label="fragment_tasks"
        tools:layout="@layout/fragment_tasks" />
    <fragment
        android:id="@+id/petFragment2"
        android:name="com.android.petdiary.presentation.view.PetFragment"
        android:label="fragment_pet"
        tools:layout="@layout/fragment_pet" />
</navigation>