diff --git a/lib/webadmin/router/config.js b/lib/webadmin/router/config.js
index 90a365b..dc81bf7 100644
--- a/lib/webadmin/router/config.js
+++ b/lib/webadmin/router/config.js
@@ -78,7 +78,7 @@ async function modemAdd(req, res) {
         name: (req.body.name || '').trim(),
         imsi: (req.body.imsi || '').trim(),
         outgoing: !!req.body.outgoing,
-        prefix: (req.body.prefix || '').split(/[, ]+/)
+        prefix: (req.body.prefix || '').trim().split(/[, ]+/)
             .map((val) => val.trim().replace(/^0/, '62'))
             .filter((row) => row),
     };
@@ -100,7 +100,7 @@ async function modemAdd(req, res) {
 
 async function modemAddPrefix(req, res) {
     const modemName = (req.body.name || '').trim();
-    const prefix = (req.body.prefix || '').split(/[, ]+/)
+    const prefix = (req.body.prefix || '').trim().split(/[, ]+/)
         .map((val) => val.trim().replace(/^0/, '62'))
         .filter((row) => row);