diff --git a/osc/conf.py b/osc/conf.py
index 4f6ea4bc..77f10057 100644
--- a/osc/conf.py
+++ b/osc/conf.py
@@ -179,7 +179,7 @@ class OscOptions(BaseModel):
 
         if not value.strip():
             if field.is_optional:
-                setattr(self, field_name, value)
+                setattr(self, field_name, None)
                 return
 
         if field.origin_type is Password: