diff --git a/app/boxes.py b/app/boxes.py
index 90e70d7..be88b32 100644
--- a/app/boxes.py
+++ b/app/boxes.py
@@ -454,24 +454,28 @@ async def get_outbox_object_by_ap_id(
     db_session: AsyncSession, ap_id: str
 ) -> models.OutboxObject | None:
     return (
-        await db_session.execute(
-            select(models.OutboxObject)
-            .where(models.OutboxObject.ap_id == ap_id)
-            .options(
-                joinedload(models.OutboxObject.outbox_object_attachments).options(
-                    joinedload(models.OutboxObjectAttachment.upload)
-                ),
-                joinedload(models.OutboxObject.relates_to_inbox_object).options(
-                    joinedload(models.InboxObject.actor),
-                ),
-                joinedload(models.OutboxObject.relates_to_outbox_object).options(
+        (
+            await db_session.execute(
+                select(models.OutboxObject)
+                .where(models.OutboxObject.ap_id == ap_id)
+                .options(
                     joinedload(models.OutboxObject.outbox_object_attachments).options(
                         joinedload(models.OutboxObjectAttachment.upload)
                     ),
-                ),
+                    joinedload(models.OutboxObject.relates_to_inbox_object).options(
+                        joinedload(models.InboxObject.actor),
+                    ),
+                    joinedload(models.OutboxObject.relates_to_outbox_object).options(
+                        joinedload(
+                            models.OutboxObject.outbox_object_attachments
+                        ).options(joinedload(models.OutboxObjectAttachment.upload)),
+                    ),
+                )
             )
         )
-    ).scalar_one_or_none()  # type: ignore
+        .unique()
+        .scalar_one_or_none()
+    )  # type: ignore
 
 
 async def get_anybox_object_by_ap_id(