It seems that due to yesterday’s Cloudflare problem (https://blog.cloudflare.com/cloudflare-outage/) netstats agent on your xDai validator nodes disconnected from https://dai-netstat.poa.network. They’re still mining blocks, but are not visible in the netstats list.
To restart the agent, please login to your node and run
sudo systemctl restart poa-netstats
then check https://dai-netstat.poa.network