Kotlin Variable changes are not applied in method and observer

Question

private var enableBottomSheet = false

bottomSheetStack.observe(requireActivity()) { stack ->
    logd("========= enableBottomSheet: ${enableBottomSheet}")
    showBottomSheet(stack)
}

override fun setMenuVisibility(menuVisible: Boolean) {
    super.setMenuVisibility(menuVisible)
    enableBottomSheet = menuVisible

    lifecycleScope.launch{
        repeat(100){
            logd("==== TIME($it): enableBottomSheet $enableBottomSheet")
            delay(100L)
        }
    }

    if (menuVisible) {
        viewModel.apiCall()
    }else{
        bottomSheetJob?.cancel()
    }
}

    private fun showBottomSheet(stack: Stack<BottomSheetStatusModel>) {
        logd("====== http showBottomSheet enableBottomSheet: ${enableBottomSheet}")
        if(!enableBottomSheet) return

        if (stack.size > 0) {
            try {
                bottomSheetJob = lifecycleScope.launch {
                    delay(100L)
                    try {
                        findNavController().navigate(R.id.action_mainContainerFragment_to_statusBottomSheet, bundle, null)
                    }catch (e: java.lang.Exception){
                        e.printStackTrace()
                    }
                }
            } catch (e: java.lang.Exception) {
                e.printStackTrace()
            }
        }
    }

And I got this result:

================ http setMenuVisibility enableBottomSheet: true ================
 ==== TIME(0): enableBottomSheet true
...
========= http enableBottomSheet: false
 ==== TIME(13): enableBottomSheet true
...
 ==== TIME(22): enableBottomSheet true
====== http showBottomSheet enableBottomSheet: false
...
 ==== TIME(99): enableBottomSheet true

There is no part that assigns false value to the enableBottomSheet. I don't know why enableBottomSheet keeps getting false.

It happens when I go like A_Fragment(A1_Fragment) -> B_Fragment -> A_Fragment(A1_Fragment) -> A_Fragment(A2_Fragment uses the code above).

(A_Fragment is the parent fragment that contains A1~A2_Fragment as ViewPager2. B_Fragment is a fragment that can go from A1_Fragment.)

Why is it happened?