Why there's unapplied balance in AR payment report?

Hi professionals,

I run AR Payment report per payment to see details which invoices or journals that has been applied to each payment received from customer. All the balance are zero, show match between payments to invoices or journals. But there's one payment entry that still has remaining balance of unapplied payment.
I keep looking where in the transaction that not linked or unapplied to invoices & journals, while when I create payment transaction, I have checked all corresponding invoices and journals to match with the amount I received, and after I save it, the status now "Deposited". Please see attached for the screen shot.