sudo apt-get update shows this messages...Unit packagekit.service not found

Failed to start esm-cache.service: Unit sysinit.target not found.Get:1 file:/var/cudnn-local-repo-ubuntu2004-8.9.4.25  InRelease [1,572 B]Get:1 file:/var/cudnn-local-repo-ubuntu2004-8.9.4.25  InRelease [1,572 B]Hit:2 https://download.docker.com/linux/ubuntu focal InRelease                                             Get:3 https://nvidia.github.io/libnvidia-container/stable/ubuntu18.04/amd64  InRelease [1,484 B]           Hit:4 https://nvidia.github.io/nvidia-container-runtime/stable/ubuntu18.04/amd64  InRelease                Hit:5 https://nvidia.github.io/nvidia-docker/ubuntu18.04/amd64  InRelease                                  Hit:6 http://security.ubuntu.com/ubuntu focal-security InRelease                           Hit:7 http://kr.archive.ubuntu.com/ubuntu focal InRelease                    Hit:8 http://kr.archive.ubuntu.com/ubuntu focal-updates InReleaseHit:9 http://kr.archive.ubuntu.com/ubuntu focal-backports InReleaseFetched 1,484 B in 2s (811 B/s)Error: GDBus.Error:org.freedesktop.systemd1.NoSuchUnit: Unit packagekit.service not found.Reading package lists... Done

What do I have to do for this?... I have no idea

P.S. I was trying to run a Docker and it was not starting with:

sudo service docker start"Failed to start docker.service: Unit sysinit.target not found."

this message...

• this is a SSH server