Cannot rebuild following site failure: "postgres already running"

As per another topic, docker ps shows the following:

/$ docker ps
CONTAINER ID        IMAGE                        COMMAND             CREATED             STATUS              PORTS                                                            NAMES
570f65df6a38        local_discourse/app:latest   "/sbin/runit"       3 months ago        Up 25 hours         0.0.0.0:80->80/tcp, 0.0.0.0:443->443/tcp, 0.0.0.0:2222->22/tcp   determined_pike

So I ran docker kill 570f65df6a38.

It now appears to be rebuilding…