diff --git a/src/worker.py b/src/worker.py
index 90ab531..8e2d8a7 100644
--- a/src/worker.py
+++ b/src/worker.py
@@ -43,7 +43,7 @@ def create_archive_task(self, archive_json: str):
         logger.error(e)
         logger.error(traceback.format_exc())
         return {"error": e}
-    return result.to_json()
+    return result.to_dict()
 
 
 @celery.task(name="create_sheet_task", bind=True, autoretry_for=(Exception,), retry_backoff=True, retry_kwargs={'max_retries': 0})