I have had an xfinity service person set up my router and it works fine. How do I remove the old name from visible networks??

Thank you for reaching out here. The quickest way to view and/or change your WiFi network name and password is to use the WiFi Details feature in the Xfinity app. 

1. Select the WiFi tab, then WiFi details.
2. Select Edit WiFi settings at the bottom.
3. On this screen, you can view or change your WiFi name or WiFi password.
4. Click Save after making any changes.