We are using the SIM intergration and it seems like more and more frequently errors are occuring after a client makes a payment. We have narrowed it down to being that the invoice nubmer is null at that time. We have not made any changes in this area in years so why is this happening more and more and what can we do to fix it?
In the transaction details in the Auth.NET account the invoice number is there. It just appears to not be properly sent back to us via the AuthorizeNet.SIMResponse.
