Invoice discount

Hi

I have two invoices where the supplier at header level is setup to always take discount but not at the site level.

Invoice is created for the supplier for who header has been set to always take discount and for a 10day payment term. At the time there are several credits for this suipplier so when the first payment process runs it does not pick this invoice for payment.

But the after that first payment there are still an outstanding invoice amount, in the second payment process the first 10day term has passed and the payment defaults to 60day term .It is setup to go to 60day if it is not paid in that first 10days.