Got it, thank you.

I do have one further question though. I'm seeing some irregular behavior for some customers. For most customers the pattern is consistent. Invoice, payment, invoice, payment. However, for some customers, it's shuffled. Where the payment for an invoice is further in the list for some reason.

 Upon further inspection it looks like it's ordered by date. If I account for this by sorting by a blank column, it fixes it, but it seems like bulk checks, ones that pay for multiple invoices, are not accounted for. So those invoices are listed as paid with no payment underneath. How can I fix that?