Help!

My standard practice is to invoice as soon a item sells, then if payment not received I re-invoice 1 day later. Both of these state "Immediate Payment received". After that Unpaid Item Assistant kicks in on day 4. -- NO EXCEPTIONS

However, I have a buyer who bought 2 items and I sent a combined invoice. I cannot see any way to re-send this invoice.

Can anyone tell me how to re-invoice on a combined sale?

Many thanks

Robert