Cancel Method
Cancels an invoice.
Syntax
[VB.NET] Public Sub Cancel(ByVal invoiceId As String)
[C#] public void Cancel(string invoiceId);
Remarks
This method is used to cancel the invoice specified by invoiceId.
CancellationInfo can be used to specify details about the invoice cancellation.
After calling this method, the Ack property will indicate success or failure.