diff --git a/static/juice.js b/static/juice.js
index 7045383..e1de1e7 100644
--- a/static/juice.js
+++ b/static/juice.js
@@ -71,7 +71,7 @@ function save_field(field) {
 	let device_id = field.parentElement.id;
 	let sub_dev_id;
 	if (field.parentElement.className.includes('sub_device')) {
-		sub_dev_id = device_id;
+		sub_dev_id = field.parentElement.children[0].textContent;
 		device_id = field.parentElement.parentElement.parentElement.id;
 	} else {
 		sub_dev_id = '';