@bottomlineusa 

"If you add all the invoices listed under the payment, they do not match the payment amount."

That's true only if you apply the payments to multiple invoices without applying the payment to the open invoice balance in full.  Your screenshot appears to show you received a payment of $2,040.52 and applied it to 19(!) different invoices.  Is there a reason you don't apply the payment to the oldest invoices first?  That's the generally accepted hierarchy of applying payments to open invoices.  Just curious.