diff --git a/app/mailboxes/reply_mailbox.rb b/app/mailboxes/reply_mailbox.rb
index 82181ad3b..d60533856 100644
--- a/app/mailboxes/reply_mailbox.rb
+++ b/app/mailboxes/reply_mailbox.rb
@@ -83,7 +83,7 @@ class ReplyMailbox < ApplicationMailbox
   end
 
   def validate_resource(resource)
-    raise "#{resource.class.name} not found" if resource.nil?
+    raise "Email conversation with uuid: #{conversation_uuid} not found" if resource.nil?
 
     resource
   end