diff --git a/setra_client/models.py b/setra_client/models.py
index 6cc9a3140ba9e8fe8f66a14ca0ffa607e55e7cea..2ca0f56291993e21a040122a8fc2d7bd24861d5c 100644
--- a/setra_client/models.py
+++ b/setra_client/models.py
@@ -194,10 +194,10 @@ class CompleteBatch(BaseModel):
     """Model for the /batch_complete/<id> endpoint"""
     created: datetime.datetime
     batchid: str
-    period: int
+    period: Optional[int]
     interface: str
     client: str
-    vouchertype: str
+    vouchertype: Optional[str]
     batch_validated_ok_date: Optional[datetime.datetime]
     batch_rejected_code: Optional[str]
     sent_date: Optional[datetime.datetime]