My client's site recorded this item as complete with the recorded credit card. However, Authorize.net claims to have no record of this transaction and the event registree says that she has no record of the transaction from card provider. The site is running Civi 5.13 on Wordpress 5.2. I'll take any suggestions on how to track this down and prevent if from happening again. For the record, this is not multisite. There are no other accounts or processors available for this site.