Android kotlin dialog transparent background blur not working

Question

I made an Android alert dialog I hope the background will be treated as a blur. It works normally on the api 32 device, but it doesn't work on the api 34 device What is the problem?

this is api34

this is api32

   <style name="RoundedDialog" parent="Theme.AppCompat.Light.Dialog.Alert">
    <item name="android:background">@drawable/rounded_background_main_color</item>
</style>


 ---@drawable/rounded_background_main_color---
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle">
<corners
    android:topLeftRadius="20dp"
    android:topRightRadius="20dp"
    android:bottomLeftRadius="20dp"
    android:bottomRightRadius="20dp"/>
<solid android:color="@color/main_color" />

     val builder = AlertDialog.Builder(thisContext, R.style.RoundedDialog)
    builder.setTitle("삭제 확인")
        .setMessage("정말 " + item.model.title + "을/를 삭제하시겠습니까?")
        .setPositiveButton("확인",
            DialogInterface.OnClickListener { dialog, id ->

                viewModelScope.launch(Dispatchers.IO) {
                    db.myDao().delete(item)
                }
                deleteItem(item.id)
                val list = _mutableRecipeListModel.value!!
                list.removeAt(position)
                _mutableRecipeListModel.value = list

            })
        .setNegativeButton("취소",
            DialogInterface.OnClickListener { dialog, id ->
            })
    builder.show()