fix: hold PO item ref in SCO Service Item
diff --git a/erpnext/buying/doctype/purchase_order/purchase_order.py b/erpnext/buying/doctype/purchase_order/purchase_order.py
index 5db048e..7f764e9 100644
--- a/erpnext/buying/doctype/purchase_order/purchase_order.py
+++ b/erpnext/buying/doctype/purchase_order/purchase_order.py
@@ -747,7 +747,9 @@
 			},
 			"Purchase Order Item": {
 				"doctype": "Subcontracting Order Service Item",
-				"field_map": {},
+				"field_map": {
+					"name": "purchase_order_item",
+				},
 				"field_no_map": [],
 			},
 		},