I have an CNAME record that appeared after a restore that I can’t delete via control panel. Any ideas how to remove?
When I attempt to delete I get this popup
Alento helped me edit the record out of my zone files, but after a reboot the problem is back. We assume the record is stored somewhere else…
You will need to remove it from zone files and the CNAME RECORD IN THE sqlite db file, not the whole SQLite DB file!!! I think? I believe MIAB has a database file sitting in /home/user-data/
My thoughts exactly @murgero … the question is HOW? 
We removed it from the zone files, but I presume that they are repopulated from the database as the entries reappeared.
First, we are going to try removing it with the API … not sure if it will work or not.
It’s in a text file at /home/user-data/dns/custom.yaml.
@alento Looks like It is using YAML files in this case.
But sort of on topic, sqlite files can be edited with https://sqlitebrowser.org/ which works on both Linux and Windows (Linux requires the use of a Desktop Environment.)
As you can notice in the screenshot the offending CNAME record was malformed. It was not possible to remove from the admin area with the delete link. Clicking the delete link returned the error as seen in the second image.
However removing the record with the API did work using the example for removing the CNAME record found in the Custom DNS API Examples!
Thanks again @alento for all your help. What I struggled with for 2 days, you were able to diagnose and fix in 20mins.
I just wanted to say that I experienced this problem myself. It was down to missing the trailing . off the domain when creating the CNAME entry.
My fix was to go into the YAML file that @JoshData mentioned
/home/user-data/dns/custom.yaml
and edit it using nano
I added the trailing . so that www.example.net became www.example.net.
Once I did this I was able to go into the custom DNS page and delete the entry properly.