diff --git a/app/models/user.rb b/app/models/user.rb
--- a/app/models/user.rb
+++ b/app/models/user.rb
@@ -320,9 +320,9 @@
     problem.uniq!.sort! do |a,b|
       case
       when a.date_added < b.date_added
-        -1
+        1
       when a.date_added > b.date_added
-        1
+        -1
       else
         a.name <=> b.name
       end