diff --git a/src/pretix/api/views/order.py b/src/pretix/api/views/order.py
index 75459370b9..8e47ba2f75 100644
--- a/src/pretix/api/views/order.py
+++ b/src/pretix/api/views/order.py
@@ -707,7 +707,7 @@ class EventOrderViewSet(OrderViewSetMixin, viewsets.ModelViewSet):
             )
 
     def create(self, request, *args, **kwargs):
-        if 'send_mail' in request.data and 'send_email' not in request.data:
+        if 'send_mail' in request.data and 'send_email' not in request.data and isinstance(request.data, dict):
             request.data['send_email'] = request.data['send_mail']
         serializer = OrderCreateSerializer(data=request.data, context=self.get_serializer_context())
         serializer.is_valid(raise_exception=True)