diff --git a/app/models/group.rb b/app/models/group.rb
index eb5c666554627baf0f7b26f0fb9c03eb3541cae0..03cc58e928c4072e9cd6a127605dbe632ca3892d 100644
--- a/app/models/group.rb
+++ b/app/models/group.rb
@@ -135,7 +135,8 @@ def has_master?(user)
   end
 
   def last_owner?(user)
-    has_owner?(user) && owners.size == 1
+    # make sure not to use cached information
+    members.owners.size == 1 && members.owners.where(user_id: user).any?
   end
 
   def avatar_type