My Sonos Play:1 gets lost to my home system every time the Sonos app is updated on my phone. Interestingly my Sonos One players stay in the network but the Play:1 is only visible if it is connected via ethernet cable. If I reset the speaker and add it connected via cable, in the process the speaker is updated as well and after another reset I can add it again via wifi. This is a very tedious procedure considering that there are usually multiple updates per month.
Currently (App release 80.24.32-release+20250717.e5bcd8b) even this solution does not work, so that I can use my Play:1 only hardwired (which is pretty idiotic for a wifi-speaker)