diff --git a/erpnext/patches/v12_0/update_ewaybill_field_position.py b/erpnext/patches/v12_0/update_ewaybill_field_position.py
index d0291d2..c0230c4 100644
--- a/erpnext/patches/v12_0/update_ewaybill_field_position.py
+++ b/erpnext/patches/v12_0/update_ewaybill_field_position.py
@@ -10,18 +10,19 @@
 
 	field = frappe.db.get_value("Custom Field", {"dt": "Sales Invoice", "fieldname": "ewaybill"})
 
-	ewaybill_field = frappe.get_doc("Custom Field", field)
+	if field:
+		ewaybill_field = frappe.get_doc("Custom Field", field)
 
-	ewaybill_field.flags.ignore_validate = True
+		ewaybill_field.flags.ignore_validate = True
 
-	ewaybill_field.update({
-		'fieldname': 'ewaybill',
-		'label': 'e-Way Bill No.',
-		'fieldtype': 'Data',
-		'depends_on': 'eval:(doc.docstatus === 1)',
-		'allow_on_submit': 1,
-		'insert_after': 'tax_id',
-		'translatable': 0
-	})
+		ewaybill_field.update({
+			'fieldname': 'ewaybill',
+			'label': 'e-Way Bill No.',
+			'fieldtype': 'Data',
+			'depends_on': 'eval:(doc.docstatus === 1)',
+			'allow_on_submit': 1,
+			'insert_after': 'tax_id',
+			'translatable': 0
+		})
 
-	ewaybill_field.save()
\ No newline at end of file
+		ewaybill_field.save()
\ No newline at end of file