Aha, so you are probably using this: discourse_docker/templates/cloudflare.template.yml at master · discourse/discourse_docker · GitHub
And it’s probably broken, since it’s 1 year old, and we updated nginx in the mean time, and don’t really use cloudfare.
I would disable this cloudfare thing, get everything backup, and then try again with time.
You will need to disable cloudfare magic in their console too.