I had a similar issue too. Tailscale messed up my resolv.conf and I rebuilt it to get basic dns working.
What I would do is look for a basic dns tutorial for Ubuntu to ensure either the local or remote dns server is working. Before you do that verify the internet is working by pinging something like 1.1.1.1 or 8.8.8.8 just as a sanity test. If that works then DNS is the last thing to get going.
Yup or colo is full and won’t accept any more changes. So one has to wait until someone else gives up space and then a fire sale on the newly freed space.