Handle empty transactions response

handler/sinks/nordigen.py

@@ -355,7 +355,11 @@ class Nordigen(util.Base):
         except ValidationError as err:
             self.log.error(f"Validation error: {err}")
             return
-        parsed = obj.to_dict()["transactions"]["booked"]
+        parsed_obj = obj.to_dict()
+        if "transactions" not in parsed_obj:
+            self.log.warning(f"No transactions for account: {account_id}")
+            return {}
+        parsed = parsed_obj["transactions"]["booked"]
         self.normalise_transactions(parsed)
         return parsed