When we attempt to process payments using the Hosted Payment Form, all transaction are returning 'Unexpected error. Please try again.' upon clicking pay.

We are utilizing the .NET SDK with package v2.0.1.
Our transaction requestion is as follows:

Dim transactionRequest As New transactionRequestType() With {
.amount = AuditRecord.Amount,
.transactionType = transactionTypeEnum.authCaptureTransaction.ToString,
.poNumber = AuditRecord.Id,
.order = New orderType() With {.invoiceNumber = Left(AuditRecord.InvoiceNumbers, 20), .description = .invoiceNumber}}

We are getting the successful token and presenting the form. However, upon entring test card information the form is invalid with 'Unexpected error. Please try again.'
We have tried all test card varieties (Visa, Master,Discover, etc)