This is likely a multicast issue.I reset one of my HomePods and received this message once it completed:
View attachment 1901450
The “Learn More” link takes you here:
Use your HomePod on an 802.1X Wi-Fi network - Apple Support
HomePod can connect to many campus or business 802.1X Wi-Fi networks. Learn which networks are supported and how to connect.support.apple.com
Nothing has changed on my end with our home network…
What’s your network/Wi-Fi configuration?
This is a great app to test what’s working and what isn’t, with regards to multicast.

Discovery - DNS-SD Browser
Discovery is a utility that displays all of the Bonjour services available on the local network or on Wide-Area Bonjour domains. Use it to debug your latest program, detect computers connected to your network, or just keep tabs on what services are available. Perfect for network admins or...
