Orders Marked as "Failed" but they are charged.

HI there-
I recently took over a site http://collegiategolfclubs.com In the backend of eshop where it shows the status of the orders, all are in the “Failed” section. HOwever Authorize.net has been processing them and customers have been getting their orders. I am told no one has been in the backend, they do not handle orders that way, just letting Authorize.net do the work. Why would they be going to “Failed”

Thanks

http://wordpress.org/extend/plugins/eshop/