This problem occurred on VPS with Ubuntu 18.04 / Debain 10
We have a web hosting service. This problem came to our customers
We used only the following two commands to fix this
sudo apt-get update
sudo apt upgrade
I faced this problem too. From what I can recall, I had to stop hestia service, make sure nginx was stopped too (I think I had to kill it because it wasn’t stopping) and then started hestia service. After that all went well.
It was some time ago and I didn’t document what I did, so I’m sorry I can’t provide more accurate information