How do I correct this error "PCI :: Error during transaction"?

This form is a contract we use with 3 way to pay.  The check portion and the pre-paid portion of the form works correctly.  When I do the credit card portion of the form, I get this error message "PCI :: Error during transaction".  We use Authorize.net and I have verified that the integration is set up correctly.  When I complete the form answering all the questions and enter my credit card info to test the credit card portion of the form, I get this error. It then tells me to go back and fix this, but when I hit the link to go back, it sends me to a blank form and I don't know what the error is so I can fix it. 

As I check the error message, I see that the issue seems to be with the Transaction key in the Authorize.net account. Could you try generating a new Transaction key in your authorize.net account as provided in the guide below and change it in the form to see if that works?

https://support.authorize.net/authkb/index?page=content&id=A569

Please get back to us if the issue still persists. We will be happy to assist.