TV disconnect

I have Xinity wifi and tv.  One of my TV's "Living Room" is showing disconnected, while my other TV, Laptop and phone are all connected.  When trying to reconnect it, it is asking me for a WPA2 passphrase, which I don't have or remember.  I've tried your Chat, your Internet troubleshoot, did a restart TV box, and a system refresh.  I'm told the connect is at 120%.  I need help to get this TV reconnected.  My account # is [Edited: "Personal Information"].   Your help would be appreciated.