diff --git a/src/backend/app/db/db_models.py b/src/backend/app/db/db_models.py
index e4f22d9bd3..bf5a9bab34 100644
--- a/src/backend/app/db/db_models.py
+++ b/src/backend/app/db/db_models.py
@@ -371,7 +371,7 @@ class DbTaskHistory(Base):
     invalidation_history = relationship(
         DbTaskInvalidationHistory, lazy="dynamic", cascade="all"
     )
-    actioned_by = relationship(DbUser)
+    actioned_by = relationship(DbUser, overlaps="task_history_user,user")
     task_mapping_issues = relationship(DbTaskMappingIssue, cascade="all")
 
     __table_args__ = (
diff --git a/src/backend/app/s3.py b/src/backend/app/s3.py
index 0e3acd76e9..b76297dd5f 100644
--- a/src/backend/app/s3.py
+++ b/src/backend/app/s3.py
@@ -3,7 +3,7 @@
 import json
 import sys
 from io import BytesIO
-from typing import Any
+from typing import Any, Optional
 
 from loguru import logger as log
 from minio import Minio
@@ -93,7 +93,7 @@ def get_file_from_bucket(bucket_name: str, s3_path: str, file_path: str):
     client.fget_object(bucket_name, s3_path, file_path)
 
 
-def get_obj_from_bucket(bucket_name: str, s3_path: str) -> BytesIO:
+def get_obj_from_bucket(bucket_name: str, s3_path: str) -> Optional[BytesIO]:
     """Download an S3 object from a bucket and return it as a BytesIO object.
 
     Args:
@@ -112,8 +112,8 @@ def get_obj_from_bucket(bucket_name: str, s3_path: str) -> BytesIO:
     try:
         response = client.get_object(bucket_name, s3_path)
         return BytesIO(response.read())
-    except Exception as e:
-        raise ValueError(str(e)) from e
+    except Exception:
+        return None
     finally:
         if response:
             response.close()
diff --git a/src/backend/app/submissions/submission_crud.py b/src/backend/app/submissions/submission_crud.py
index 03f8b5b0df..d4c255c1d1 100644
--- a/src/backend/app/submissions/submission_crud.py
+++ b/src/backend/app/submissions/submission_crud.py
@@ -358,14 +358,17 @@ def update_submission_in_s3(
         try:
             # Get the last submission date from the metadata
             file = get_obj_from_bucket(settings.S3_BUCKET_NAME, metadata_s3_path)
-            zip_file_last_submission = (json.loads(file.getvalue()))["last_submission"]
-            if last_submission <= zip_file_last_submission:
-                # Update background task status to COMPLETED
-                update_bg_task_sync = async_to_sync(
-                    project_crud.update_background_task_status_in_database
-                )
-                update_bg_task_sync(db, background_task_id, 4)  # 4 is COMPLETED
-                return
+            if file:
+                zip_file_last_submission = (json.loads(file.getvalue()))[
+                    "last_submission"
+                ]
+                if last_submission <= zip_file_last_submission:
+                    # Update background task status to COMPLETED
+                    update_bg_task_sync = async_to_sync(
+                        project_crud.update_background_task_status_in_database
+                    )
+                    update_bg_task_sync(db, background_task_id, 4)  # 4 is COMPLETED
+                    return
 
         except Exception as e:
             log.warning(str(e))