diff --git a/app/services/messaging.py b/app/services/messaging.py
index f14da37..a4e38f8 100644
--- a/app/services/messaging.py
+++ b/app/services/messaging.py
@@ -98,7 +98,8 @@ def inbox(user, page=1, per_page=20):
                 Conversation.buyer_id == user.id,
                 Conversation.seller_id == user.id,
             ))
-            .order_by(Conversation.last_message_at.desc().nullslast(),
+            .order_by(Conversation.last_message_at.is_(None),
+                      Conversation.last_message_at.desc(),
                       Conversation.created_at.desc())
             .paginate(page=page, per_page=per_page, error_out=False))