Навигация между фрагментами и разбор объектов между ними в Android

Question

У меня проблема с обработкой навигации в моем приложении, сейчас у меня исключение нулевого указателя:

        at com.lswarss.ing_project.fragments.PostsFragment.onViewCreated(PostsFragment.kt:56)
        at androidx.fragment.app.FragmentStateManager.createView(FragmentStateManager.java:332)
        at androidx.fragment.app.FragmentManager.moveToState(FragmentManager.java:1187)
        at androidx.fragment.app.FragmentManager.addAddedFragments(FragmentManager.java:2224)
        at androidx.fragment.app.FragmentManager.executeOpsTogether(FragmentManager.java:1997)
        at androidx.fragment.app.FragmentManager.removeRedundantOperationsAndExecute(FragmentManager.java:1953)
        at androidx.fragment.app.FragmentManager.execPendingActions(FragmentManager.java:1849)
        at androidx.fragment.app.FragmentManager.dispatchStateChange(FragmentManager.java:2629)
        at androidx.fragment.app.FragmentManager.dispatchActivityCreated(FragmentManager.java:2577)
        at androidx.fragment.app.Fragment.performActivityCreated(Fragment.java:2722)
        at androidx.fragment.app.FragmentStateManager.activityCreated(FragmentStateManager.java:346)
        at androidx.fragment.app.FragmentManager.moveToState(FragmentManager.java:1188)
        at androidx.fragment.app.FragmentManager.moveToState(FragmentManager.java:1356)
        at androidx.fragment.app.FragmentManager.moveFragmentToExpectedState(FragmentManager.java:1434)
        at androidx.fragment.app.FragmentManager.moveToState(FragmentManager.java:1497)
        at androidx.fragment.app.FragmentManager.dispatchStateChange(FragmentManager.java:2625)
        at androidx.fragment.app.FragmentManager.dispatchActivityCreated(FragmentManager.java:2577)
        at androidx.fragment.app.FragmentController.dispatchActivityCreated(FragmentController.java:247)
        at androidx.fragment.app.FragmentActivity.onStart(FragmentActivity.java:541)
        at androidx.appcompat.app.AppCompatActivity.onStart(AppCompatActivity.java:201)
        at android.app.Instrumentation.callActivityOnStart(Instrumentation.java:1514)
        at android.app.Activity.performStart(Activity.java:7838)
        at android.app.ActivityThread.handleStartActivity(ActivityThread.java:3398)
        at android.app.servertransaction.TransactionExecutor.performLifecycleSequence(TransactionExecutor.java:221)
        at android.app.servertransaction.TransactionExecutor.cycleToPath(TransactionExecutor.java:201)
        at android.app.servertransaction.TransactionExecutor.executeLifecycleState(TransactionExecutor.java:173)
        at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:97)
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2109)
        at android.os.Handler.dispatchMessage(Handler.java:107)
        at android.os.Looper.loop(Looper.java:214)
        at android.app.ActivityThread.main(ActivityThread.java:7682)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:516)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:950)```

It throws on my PostsFragment function navigation: 

class PostsFragment : Fragment(), View.OnClickListener {

    private val viewModel : PostsViewModel by lazy {
        ViewModelProvider(this).get(PostsViewModel::class.java)
    }

    lateinit var navController: NavController

    private val adapter = PostsAdapter()

    override fun onCreateView(
        inflater: LayoutInflater,
        container: ViewGroup?,
        savedInstanceState: Bundle?
    ): View? {
        val binding = PostsFragmentBinding.inflate(inflater)
        binding.setLifecycleOwner(this)

        binding.viewModel = viewModel

        viewModel.posts.observe(viewLifecycleOwner, Observer {
            adapter.submitList(it)
        })

        binding.recyclerViewPosts.adapter = adapter
        return binding.root
    }

    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
        super.onViewCreated(view, savedInstanceState)
        navController = Navigation.findNavController(view)
        view.findViewById<TextView>(R.id.post_comment).setOnClickListener(this)
        view.findViewById<TextView>(R.id.post_user).setOnClickListener(this)
    }

    override fun onClick(v: View?) {
        when(v!!.id){
            R.id.post_user -> {
                val bundle = bundleOf("postProperties" to UserFragmentArgs)
                navController!!.navigate(R.id.navigation_to_user)
            }
            R.id.post_comment -> {
                val bundle = bundleOf("postProperties" to CommentsFragmentArgs)
                navController!!.navigate(R.id.navigation_to_comments)
            }
        }
    }
}

Я новичок в android и думаю, что я перестал сложный и неправильно написанный мой проект. Вот ссылка на репо, если это как-то помогает, самые последние изменения находятся в ветке fragments_navigation: https://github.com/LSWarss/ing_project