fix error message for broken mails

app/helpers/mailer_helper.rb

@@ -7,7 +7,7 @@ module MailerHelper
             mail.deliver
           rescue => e
             Rails.logger.error "---"
-            Rails.logger.error "WARNING: '#{mail.try(:subject)}' failed for user #{@user.try(:name)}, #{@user.try(:email)}"
+            Rails.logger.error "WARNING: '#{mail.try(:subject)}' failed for recipient #{mail.try(:to)}"
             Rails.logger.error e.message
             Rails.logger.error "---"
           end