Hi @Neoito,
-You can pass ‘Journal Entry’ to write off sales invoice.
- At the time of creating ‘Journal Entry’ keep “Entry Type” as “Write Off Entry”
- ‘Write off’ section->
1.Write Off Based On - Accounts Receivable - ‘Get Outstanding Invoice’ and Enter Write Off amount
- first entry of Debtor (customer) account against Credit ----- select reference type and name
your second entry will be “write off” account against Debit - save and submit
- Sales Invoice status will become “Paid”.