diff --git a/app/src/main/java/fr/free/nrw/commons/upload/categories/UploadCategoriesFragment.kt b/app/src/main/java/fr/free/nrw/commons/upload/categories/UploadCategoriesFragment.kt
index 584b87963..af889467a 100644
--- a/app/src/main/java/fr/free/nrw/commons/upload/categories/UploadCategoriesFragment.kt
+++ b/app/src/main/java/fr/free/nrw/commons/upload/categories/UploadCategoriesFragment.kt
@@ -220,7 +220,7 @@ class UploadCategoriesFragment : UploadBaseFragment(), CategoriesContract.View {
     }
 
     override fun goToNextScreen() {
-        callback!!.onNextButtonClicked(callback!!.getIndexInViewFlipper(this))
+        callback?.let { it.onNextButtonClicked(it.getIndexInViewFlipper(this)) }
     }
 
     override fun showNoCategorySelected() {
@@ -322,7 +322,8 @@ class UploadCategoriesFragment : UploadBaseFragment(), CategoriesContract.View {
             mediaDetailFragment.onResume()
             goBackToPreviousScreen()
         } else {
-            callback!!.onPreviousButtonClicked(callback!!.getIndexInViewFlipper(this))
+            callback?.let { it.onPreviousButtonClicked(it.getIndexInViewFlipper(this)) }
+
         }
     }