fix: TDS check getting checked after reload (#24972)

diff --git a/erpnext/accounts/doctype/purchase_invoice/purchase_invoice.js b/erpnext/accounts/doctype/purchase_invoice/purchase_invoice.js
index 06aa20b..66a8e20 100644
--- a/erpnext/accounts/doctype/purchase_invoice/purchase_invoice.js
+++ b/erpnext/accounts/doctype/purchase_invoice/purchase_invoice.js
@@ -524,7 +524,7 @@
 	},
 
 	onload: function(frm) {
-		if(frm.doc.__onload) {
+		if(frm.doc.__onload && frm.is_new()) {
 			if(frm.doc.supplier) {
 				frm.doc.apply_tds = frm.doc.__onload.supplier_tds ? 1 : 0;
 			}