Logon to Virtual Terminal
https://secure.linkpt.net/lpc/servlet/LPCPage
Scroll over on the menu on the top of the screen pick the option ADMINISTRATION
Pick from the drop down Basic Fraud Settings Click on that
Scroll down to the bottom of the screen SET LOCK OUT TIME
Bottom portion says Duplicate Lock out Time enter an amount of minutes they want to lock duplicate transactions.
Enter 0 Minutes and press Green submit button.
Takes effect right then and there.