diff --git a/application/Contract/ContractController.php b/application/Contract/ContractController.php
index 8aab88094..1f0c05050 100644
--- a/application/Contract/ContractController.php
+++ b/application/Contract/ContractController.php
@@ -625,6 +625,8 @@ class ContractController extends mfBaseController
             $order_date->setTimezone(new DateTimeZone("Europe/Vienna"));
             $order_date->setTime(0, 0, 0);
             $contract_data['order_date'] = $order_date->getTimestamp();
+        } else {
+            $contract_data['order_date'] = null;
         }
 
         if($r->finish_date) {
@@ -632,6 +634,8 @@ class ContractController extends mfBaseController
             $finish_date->setTimezone(new DateTimeZone("Europe/Vienna"));
             $finish_date->setTime(0, 0, 0);
             $contract_data['finish_date'] = $finish_date->getTimestamp();
+        }  else {
+            $contract_data['finish_date'] = null;
         }
 
         if($r->cancel_date) {
@@ -639,6 +643,8 @@ class ContractController extends mfBaseController
             $cancel_date->setTimezone(new DateTimeZone("Europe/Vienna"));
             $cancel_date->setTime(0, 0, 0);
             $contract_data['cancel_date'] = $cancel_date->getTimestamp();
+        } else {
+            $contract_data['cancel_date'] = null;
         }