I tried following the advice in a previous answer, but could not reinstall gnome, and have listed the result of my effort.
jack@jack-ThinkCentre-M58p:~$ sudo apt-get install --reinstall gnome-control-center
E: Could not get lock /var/lib/dpkg/lock-frontend. It is held by process 12836 (unattended-upgr)
N: Be aware that removing the lock file is not a solution and may break your system.
E: Unable to acquire the dpkg frontend lock (/var/lib/dpkg/lock-frontend), is another process using it?
cocomac, think I got it here---https://askubuntu.com/questions/1237965/reporting-i-cant-open-settings-in-ubuntu-20-04-lts
sudo apt update
before doing anything else inapt
andapt-get
. You should also runsudo apt upgrade
if there are any updates pending. You don't want to make the situation worse – Nmath Dec 04 '21 at 20:29jack@jack-ThinkCentre-M58p:~$ sudo apt upgrade [sudo] password for jack: Waiting for cache lock: Could not get lock /var/lib/dpkg/lock-frontend. It is held by process 14476 (unattended-upgr)...
– oneeyedjack Dec 06 '21 at 19:22