I am using Ubuntu 20.04 LTS + Hestia Control Panel: v1.3.3
I receive corn error notification as follows;
Cron <admin@______> sudo /usr/local/hestia/bin/v-update-sys-hestia-all
W: Failed to fetch https://apt.hestiacp.com/dists/focal/InRelease Temporary failure resolving ‘apt.hestiacp.com’
W: Some index files failed to download. They have been ignored, or old ones used instead.
Do you receive it daily? If yes, check your local dns configuration, looks like you’ve a problem there. Do a nslookup apt.hestiacp.com and check the reply.
This is nothing you can fix with apt update, as written, it looks like a dns resolve issue, but could also been temporary because you just got it once.