Not really enough information to begin to guess, but I’d make sure you’re using the S1 app, as the first gen PLAY:5 will only run that, while the PLAY:1 can run either S1 or S2, just not simultaneously. But I’d recommend that you call Sonos Support directly to discuss it.

When you speak directly to the phone folks, they have tools at their disposal that will allow them to give you advice specific to your network and Sonos system.