Per the instructions in the new router - installation instructions FAQ, temporarily wire the soundbar to your router with an Ethernet cable.

I’ve connected it to the internet. My Sonos One XL in the bedroom plays music just fine. It’s the one in the living room that is connected to my TV that is not playing other than the TV sound.

Sorry, I need more detail. When you say ‘connected it to the internet’, do you mean wired to your router with an Ethernet cable, or do you mean connected wirelessly via WiFi? 

Is there any chance you factory reset one or the other (or both) Sonos devices, which may have ended up in setting up two different systems?

Have you called Sonos Support directly to discuss it?

Thank you for your help.  
 

Connected wirelessly- I followed the steps it asked when I turned on the device. Then it asked me if I wanted to add the other one to the Sonos network.  Do you think connecting it directly to the router would make a difference?

Yes, it likely would, although now I’m wondering if this Fios network has repeaters/mesh network issues that are causing the two devices to be on different subnets. 

Have you called Sonos Support?

Nope, but I will tomorrow. Thank you again!!