diff --git a/app/models/student_work.rb b/app/models/student_work.rb
index 4da23a30f..473efa756 100644
--- a/app/models/student_work.rb
+++ b/app/models/student_work.rb
@@ -105,7 +105,7 @@ class StudentWork < ApplicationRecord
   end
 
   def delete_atta atta
-    last_score = student_works_scores.where.not(score: nil).last
+    last_score = student_works_scores.last
     (atta.author_id == User.current.id) && (last_score.blank? || last_score.try(:created_at) < atta.created_on)
   end