If you run 
sudo apt update
or
sudo apt upgrade
it will break nginx - the web server that provides the control panel and VitXi.
The fix is to uninstall and reinstall nginx:
Uninstall and ReInstall NGINX on Debian 12 The Right Way | diditho.com
Then reinstall Vital PBX as per the install instruction:
Installing VitalPBX 4.5 In Debian: Easy How-To Guide
All settings and data is retained.
Keep in mind that removing NGINX will remove all the VitalPBX packages including add-ons. So, I don’t know how safe is this!
Yes it did remove add ons but I just reinstalled them. I did not find anything else broken.
Why do you say the update breaks nginx? I haven’t seen it happen on my 4.5 systems.
I just ran sudo apt update and sudo apt upgrade - nginx threw an error - stopped and would not restart. PBX was still working but without the ability to monitor or control it. I don’t know why it happened but it may happen to someone else.
We had no issue with update.
Could be due to OS and other resources.
Updated 3 system with following command, with no issue:
sudo apt clean all
sudo apt update
sudo apt upgrade -y
I saw another post in forum of a user with a similar nginx issue, might have been some issue with the people that update first. @miguel was there some sort of nginx bug that was fixed?