Error on call https://172.30.32.1:8123 - HA inaccessible nor via browser or telnet OVA installation

Hi,
After a core update, my HA became unavailable to be accessed by browser or telnet.
I’ve seen the “error on call” in “su logs” command. I’ve tried to restore several previous full backups via “backups restore”, the commands are completed successfully but the machine is still inaccessible.
HA is installed as a virtualbox (I’ve taken the available OVA from HA site).
There is no obvious error when the virtual machine starts.
I’ve found this link with some explanations, but nothing could be applied at an OVA installation, as I am limited to HA CLI:

Could someone drive me to solve this?
Thank you,