fix: incorrect outstanding on non-pos invoice with write_off_account

erpnext/accounts/doctype/sales_invoice/sales_invoice.py

@@ -338,6 +338,7 @@ def validate(self):
 		if self.redeem_loyalty_points and self.loyalty_points and not self.is_consolidated:
 			validate_loyalty_points(self, self.loyalty_points)
 
+		self.allow_write_off_only_on_pos()
 		self.reset_default_field_value("set_warehouse", "items", "warehouse")
 
 	def validate_accounts(self):
@@ -1031,6 +1032,10 @@ def validate_delivery_note(self):
 				),
 			)
 
+	def allow_write_off_only_on_pos(self):
+		if not self.is_pos and self.write_off_account:
+			self.write_off_account = None
+
 	def validate_write_off_account(self):
 		if flt(self.write_off_amount) and not self.write_off_account:
 			self.write_off_account = frappe.get_cached_value("Company", self.company, "write_off_account")