We send billing every two weeks. Invoices and statement to all of our clients have their file number on them if they provided one with the order. We do not send an invoice with each and every completed order. Asking us to do so to only placate one client is not efficient. We have found over almost 30 years of doing business that sending an invoice with a completed order, the invoice tends not be forwarded to that company's AP dept. so we end up billing again. 

I don't know about you, but this has gone on way too long for only $42.00. Please pay us so we can put this matter to bed.