Problem with VM for Perfect Server 18.04

Hi,
I downloaded the virtual machine for 18.04 with nginx.
The only real change I did to the server is installed php 5.6 as a second php based on https://www.howtoforge.com/tutorial...fig-3-from-debian-packages-on-debian-8-and-9/
Right now when I try reboot or shutdown I get "A stop job is running for Unattended Upgrades Shutdown.
A counter is displayed out of 30 min.
While it is rare, we will need to reboot the server from time to time and can't afford to wait for 30 minutes.

Any idea how we can prevent this delays?

Thanks.

 

That was it. Thank you very much.