diff --git a/modules/purchase_trade/service.py b/modules/purchase_trade/service.py
index f254c98..b723172 100644
--- a/modules/purchase_trade/service.py
+++ b/modules/purchase_trade/service.py
@@ -240,10 +240,10 @@ class ContractFactory:
             return
         line.del_period = c.del_period
         line.from_del = (
-            c.from_del
+            getattr(c, 'from_del', None)
             or getattr(getattr(c, 'del_period', None), 'beg_date', None))
         line.to_del = (
-            c.to_del
+            getattr(c, 'to_del', None)
             or getattr(getattr(c, 'del_period', None), 'end_date', None))
 
     @staticmethod
diff --git a/modules/purchase_trade/tests/test_module.py b/modules/purchase_trade/tests/test_module.py
index a5a0dee..5279059 100644
--- a/modules/purchase_trade/tests/test_module.py
+++ b/modules/purchase_trade/tests/test_module.py
@@ -2848,8 +2848,10 @@ class PurchaseTradeTestCase(ModuleTestCase):
     def test_contract_factory_delivery_dates_fallback_to_period(self):
         'hidden delivery dates are still derived from delivery period'
         period = Mock(beg_date='2026-05-01', end_date='2026-05-31')
-        contract_detail = Mock(
-            del_period=period, from_del=None, to_del=None)
+        class ContractDetailMock:
+            del_period = period
+
+        contract_detail = ContractDetailMock()
         line = Mock()
 
         ContractFactory._apply_delivery(line, contract_detail, {})