Thank you for your report. Diagnostic logging from your account confirms that there were severe network reachability errors interfering with basic RoonServer background processes, including authorization/sync to streaming services.
There are residual network reachability events after the reboot in logs, but they don’t appear to interfere with Roon’s operation.
Note that DHCP may require you to occasionally change any manual port forwarding rules you have created across your two routers for Roon ARC, since your RoonServer’s LAN IP is no longer fixed.
If you are using a Windows RoonServer machine, additionally verify that RoonServer.exe and associated processes are excepted in the Defender firewall.