Seems to be a duplicate of https://bugs.launchpad.net/ubuntu/+source/systemd/+bug/1938791 - same symptoms.
[Workaround]
Reboot the node, DNS should return back to normal.
Seems to be a duplicate of https:/ /bugs.launchpad .net/ubuntu/ +source/ systemd/ +bug/1938791 - same symptoms.
[Workaround]
Reboot the node, DNS should return back to normal.