You’ll need to disable proxy, run certbot, then re enable proxy.

LE won’t sign a site already cf encrypted, or behind cf (even with cf SSL disabled.)

You could try a DNS challenge or other method.

https://letsencrypt.org/docs/challenge-types/

In this episode of “Doing everything the hardest way possible.”

Cloudflare has SSL, y u need mo?

“unacceptable” I do not think this word means what you think it means…

Really… Really wanted to give this comment gold… 🥇