Every site is monitored twice

I installed Uptime Kuma on my ZimaBoard to watch my sites and the homelab itself. It went on port 3002 and not its default 3001, because an AdGuard install still claims 3001 in its compose file even though it has been stopped for months. The thing I nearly got wrong: every one of my domains sits behind Cloudflare. A plain HTTP check against the domain proves Cloudflare answered, not that my app is alive. A dead origin can still return a Cloudflare error page.