I hope you mean ‘losing’, and not ‘loosing’. 

Have you called 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.

With the May 2024 release of the S2 client, Sonos changed the method by which they ‘discover’ devices on the network, my guess is there is something interfering with that. Not sure if it is simple wifi interference , or a setting on your router, or an issue in one or more Sonos devices. 

Sorry about the spelling :)

It used to work fine but now it sometimes some devices get lost. Not all, just some. 

What changes did they make that could be interfering with my wifi?

It’s an easy misunderstanding, I’m just OCD about it ;)

It isn’t any change Sonos made that would be interfering with your WiFi, they are merely a client on your WiFi. However, WiFi networks are always changing, by their very nature. It could be something internal to your home, it could be something external to your home. 

The challenge is something in your network could be occasionally interrupting the discovery process that the Sonos controller runs when it starts up.