Please follow the below template, it will help us to help you!
Expected Behaviour:
admin dashboard should load correctly
Actual Behaviour:
dashboard shows "lost connection to API"
Debug Token:
4jzrp6h80w
This thread has the info you should need
Hey,
Thanks for checking but I don't think that's the issue - systemd-resolved was already disabled before I upgraded the Ubuntu version. This is how it looks now:
root@teevee:~# systemctl status systemd-resolved
ā systemd-resolved.service - Network Name Resolution
Loaded: loaded (/lib/systemd/system/systemd-resolved.service; disabled; vendor preset: enabled)
Active: inactive (dead)
Docs: man:systemd-resolved.service(8)
https://www.freedesktop.org/wiki/Software/systemd/resolved
https://www.freedesktop.org/wiki/Software/systemd/writing-network-configuration-managers
https://www.freedesktop.org/wiki/Software/systemd/writing-resolver-clients
And nothing is listening on port 53:
root@teevee:~# netstat -anp | grep 53 | grep -i listen
tcp6 0 0 :::53 :::* LISTEN 10095/docker-proxy
and I can see queries in the pihole.log
To add to the original error report (something I should have put in there originally, but oh well) - I had to start lighttpd manually via /etc/init.d/lighttpd start, it did not start automatically
something is using 53 unless that is your dockerized instance
please try from within your container sudo service pihole-FTL start
Ah, it turns out your first reply was on-point 
i implemented exactly what the article said, and now pihole works perfectly. Thanks very much for your help!
For future visitors: in Ubuntu 18.04, simply disabling systemd-resolved is not sufficient, please implement the steps in the link provided by technicalpyro