diff --git a/hb_server/apps/hrm/models.py b/hb_server/apps/hrm/models.py
index 5e95b7f..47d1dc2 100644
--- a/hb_server/apps/hrm/models.py
+++ b/hb_server/apps/hrm/models.py
@@ -35,3 +35,4 @@ class Employee(CommonAModel):
 
     def __str__(self):
         return self.name
+
diff --git a/hb_server/apps/sam/serializers.py b/hb_server/apps/sam/serializers.py
index 5c7afac..db2117e 100644
--- a/hb_server/apps/sam/serializers.py
+++ b/hb_server/apps/sam/serializers.py
@@ -38,7 +38,7 @@ class ContractSimpleSerializer(serializers.ModelSerializer):
 class ContractCreateUpdateSerializer(serializers.ModelSerializer):
     class Meta:
         model = Contract
-        fields = ['name', 'number', 'amount', 'customer', 'sign_date', 'description']
+        fields = ['name', 'number', 'amount', 'customer', 'sign_date', 'description', 'invoice']
 
 
 class OrderCreateUpdateSerializer(serializers.ModelSerializer):