Not really enough information to be certain, but it could be either simple wifi interference , or possibly a duplicate IP address issue in your router. The linked FAQ provides many possibilities, and for the latter, a simple refresh of you network might help, by unplugging you Beam from power, then rebooting your router. Give the router a couple of minutes to recover before plugging back in your Beam.
If neither of these potentials provide a solution, I would recommend that you submit a system diagnostic within 10 minutes of experiencing this problem, and call Sonos Support to discuss it. But don’t post the resulting diagnostic number here, they get sensitive about GDPR.
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 Support staff, they have tools at their disposal that will allow them to give you advice specific to your network and Sonos system.
