fix: broken set exchagne gain/loss btn broken in payment entry
diff --git a/erpnext/accounts/doctype/payment_entry/payment_entry.js b/erpnext/accounts/doctype/payment_entry/payment_entry.js
index ed6d0a7..07761c7 100644
--- a/erpnext/accounts/doctype/payment_entry/payment_entry.js
+++ b/erpnext/accounts/doctype/payment_entry/payment_entry.js
@@ -977,6 +977,7 @@
 							precision("difference_amount"));
 
 						const add_deductions = (details) => {
+							let row = null;
 							if (!write_off_row.length && difference_amount) {
 								row = frm.add_child("deductions");
 								row.account = details[account];