Kotlin Fragment not attached to a context

I have my app connected to Crashlytic and I get this error:

Fatal Exception: java.lang.IllegalStateException: Fragment ProductFragment not attached to a context.
   at androidx.fragment.app.Fragment.requireContext(Fragment.java:900)
   at androidx.fragment.app.Fragment.getResources(Fragment.java:964)
   at com.example.fragments.ProductFragment$loaditems$1.onSuccess(ProductFragment.kt:60)
   at com.example.fragments.ProductFragment$loaditems$1.onSuccess(ProductFragment.kt:21)
   at com.google.android.gms.tasks.zzn.run(:4)
   at android.os.Handler.handleCallback(Handler.java:873)
   at android.os.Handler.dispatchMessage(Handler.java:99)
   at android.os.Looper.loop(Looper.java:214)
   at android.app.ActivityThread.main(ActivityThread.java:6981)
   at java.lang.reflect.Method.invoke(Method.java)
   at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493)
   at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1445)

I never have seen my app crash, thats the weird thing. Because of this I don't know what kind of thing triggers the error.

This is my code:

package com.example.fragments

import android.os.Bundle
import androidx.fragment.app.Fragment
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
import android.widget.LinearLayout
import androidx.recyclerview.widget.GridLayoutManager
import androidx.recyclerview.widget.LinearLayoutManager
import androidx.recyclerview.widget.RecyclerView
import com.example.adapters.MyProductAdapter
import com.example.R
import com.example.models.productmodel
import com.google.firebase.firestore.ktx.firestore
import com.google.firebase.ktx.Firebase
import org.json.JSONArray
import java.io.IOException
import java.io.InputStream

class ProductFragment : Fragment() {

   private var recyclerView: RecyclerView? = null
   private var errorscreen: LinearLayout? = null
   private var loadingscreen: LinearLayout? = null
   private var gridLayoutManager: GridLayoutManager? = null
   private var arrayList: ArrayList<productmodel> ? = null
   private var adapter: MyProductAdapter? = null
   private val tabel = "producten_nl"

   override fun onCreateView(
      inflater: LayoutInflater, container: ViewGroup?,
      savedInstanceState: Bundle?
   ): View? {
      val v = inflater.inflate(R.layout.fragment_producten, container, false)

      loadingscreen = v.findViewById(R.id.productloadingscreen)
      recyclerView = v.findViewById(R.id.json_listp)
      errorscreen = v.findViewById(R.id.errorscreen)

      gridLayoutManager = GridLayoutManager(getActivity(), 2, LinearLayoutManager.VERTICAL, false)
      recyclerView?.layoutManager = gridLayoutManager
      recyclerView?.setHasFixedSize(true)
      arrayList = ArrayList()
      arrayList = loaditems()

      return v
   }

   private fun loaditems(): ArrayList<productmodel> {
      val items: ArrayList<productmodel> = ArrayList()
      val db = Firebase.firestore

      db.collection(tabel)
         .orderBy("volgorde")
         .get()
         .addOnSuccessListener { result ->
            if (result.count() != 0) {
               for (document in result) {
                  if(document.getBoolean("show") == true) {
                     val photo = resources.getIdentifier(document.getString("image"), "drawable", requireContext().packageName)
                     val name = document.getString("name") as String
                     val image = document.getString("image") as String
                     val url = document.getString("url") as String

                     items.add(productmodel(photo, name, image, url))
                  }
               }
               adapter = MyProductAdapter(requireActivity().baseContext, arrayList!!)
               recyclerView?.adapter = adapter
               recyclerView?.visibility = View.VISIBLE
               loadingscreen?.visibility = View.GONE
            }
            else
            {
               errorscreen?.visibility = View.VISIBLE
               recyclerView?.visibility = View.GONE
               loadingscreen?.visibility = View.GONE
            }
         }
         .addOnFailureListener { exception ->
            errorscreen?.visibility = View.VISIBLE
            recyclerView?.visibility = View.GONE
            loadingscreen?.visibility = View.GONE
         }
      return items
   }
}

Line 60 is this line: if(document.getBoolean("show") == true) { and line 21 is this line: class ProductFragment : Fragment() {

I don't know what this error is and what causes this error. Does anyone know what I do wrong?

Edit: This is the way I put a fragmant inside an activity

    private fun  makeCurrentFragment(fragment: Fragment) =
    supportFragmentManager.beginTransaction().apply {
        replace(R.id.fl_wrapper, fragment)
        commit()
    }