moving between fragmentsn udpate sdk to api 21, required to use navigation

CineCool/app/src/main/res/layout/fragment_session.xml

@@ -10,7 +10,7 @@
         android:id="@+id/returnButton"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
-        android:text="Button"
+        android:text="Button Sessions"
         app:layout_constraintBottom_toBottomOf="parent"
         app:layout_constraintEnd_toEndOf="parent"
         app:layout_constraintStart_toStartOf="parent"