diff --git a/module/device/connection_attr.py b/module/device/connection_attr.py
index 43a6c7c..69dc371 100644
--- a/module/device/connection_attr.py
+++ b/module/device/connection_attr.py
@@ -57,6 +57,12 @@ class ConnectionAttr:
         serial = serial.replace('。', '.').replace('，', '.').replace(',', '.').replace('：', ':')
         # 127.0.0.1.5555
         serial = serial.replace('127.0.0.1.', '127.0.0.1:')
+        # Mumu12 5.0 shows double serials, some people may just copy-paste it
+        # 5555,16384
+        if ',' in serial:
+            left, _, right = serial.partition(',')
+            if left.startswith('55') and right.startswith('16'):
+                serial = right
         # 16384
         try:
             port = int(serial)