diff --git a/src/shop/views.py b/src/shop/views.py
index bd6c785e..2bce03f5 100644
--- a/src/shop/views.py
+++ b/src/shop/views.py
@@ -277,13 +277,7 @@ class OrderListView(LoginRequiredMixin, ListView):
         return queryset.filter(user=self.request.user).not_cancelled()
 
 
-class OrderDetailView(
-    LoginRequiredMixin,
-    EnsureUserOwnsOrderMixin,
-    EnsureOrderHasProductsMixin,
-    EnsureOrderIsNotCancelledMixin,
-    DetailView
-):
+class OrderDetailView(LoginRequiredMixin, EnsureUserOwnsOrderMixin, EnsureOrderHasProductsMixin, EnsureOrderIsNotCancelledMixin, DetailView):
     model = Order
     template_name = 'order_detail.html'
     context_object_name = 'order'
@@ -300,7 +294,7 @@ class OrderDetailView(
             # Set payment method and mark the order as closed
             order.payment_method = payment_method
             order.open = None
-            order.customer_comment = request.POST.get('customer_comment')
+            order.customer_comment = request.POST.get('customer_comment') or ''
             order.save()
 
             reverses = {
@@ -331,7 +325,7 @@ class OrderDetailView(
                     new_quantity = int(request.POST.get(order_product_id))
                     order_product.quantity = new_quantity
                     order_product.save()
-            order.customer_comment = request.POST.get('customer_comment')
+            order.customer_comment = request.POST.get('customer_comment') or ''
             order.save()
 
         product_remove = request.POST.get('remove_product')