App Center error because of deactivated docker service


after deactivating the docker service (Problem: containerd is running even docker is disabled), I get an error, each time starting the App Center. I get also an error when installing an app (nonetheless is that app/service working after that error) because of the missing docker service. Did I missed something when deactivating docker?

ucr set docker/autostart=no
systemctl disable containerd

I just recognized that there is a package named univention-appcenter-docker installed. Could it help to remove that package or does it make things worser?