Try this order 

Torn of all devices that connect to your WiFi. Then all that have Ethernet  connections. Now reboot router. 
 

then start up devices strong with the Sonos devices. Once all complete then try the app. 
 

let us know of this works

The app recognizes the Bridge but not the Paybar.

The Playbar is plugged into th wall socket, but no lights on it and no indication why it does not getr electricity.

Any ideas?

Try plugging the PLAYBAR into another outlet. 

It’s also possible the PLAYBAR has failed, if so, you should call Sonos Support directly to discuss it.

When you speak directly to the phone folks, there are more options available for them to assist you.

Thank you!