Hi I am seeing the same problem
it’s lucky dip when I try to use the App
i have 4 Sonos devices Amp/ Port / Play5 and Move
Some days all show , others just 1 and it’s never the same one.
Yet if I then go to my MacAir M2 all the devices show
Also I’ve set my Sonos to Google home and if I ask Google to play on any of the Sonos devices it works.
As an aside if I do use the Mac App then go to iPhone app the devices miraculously appear.
my IPhone 12Pro is on the latest iOS 16.3.1
the Sonos App is 15.1
all on the same WiFi no mesh no clever stuff. It’s clearly the App
Come on Sonos give us back the bullet proof App we used to have
As that is not the case right now