How can i write-off the amount through Payment Entry

i create a sales invoice with “10,000” and submitted.
now i created a payment entry of “8000” through the reference of sales invoice.
I want to write-off the remaining “2000”.
how can do it ?

Create a new Journal Entry with the receiveable account and write-off account against each other and then reconcile the customer Sales Invoice via Payment Reconciliation.

thank you for suggesting, now outstanding from “2000” to “0” and status converted into paid but how i know that “2000” is an write-off amount for this sales invoice?

Now i want to refund the “3000” to the customer let me know the process.