sonos arc loosing wifi connection

You haven’t given us much information to work on, unfortunately. And I’m assuming it isn’t showing up in your Sonos controller device when you are ‘loosing’ (sic) the connection?

What kind of network is it connected to? Have you tried connecting it via Ethernet cable? Have you submitted a system diagnostic within 10 minutes of experiencing this problem, and called Sonos Support to discuss it?

There may be information included in the diagnostic that will help Sonos pinpoint the issue and help you find a solution.

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.