Communication error with letencrypt server

Lol!
Oups.
Currently, I define some container for reverse proxy. I copy sample file for heimdall, jellyfin, portainer and syncrhing and I remove the .sample at the end of the file name.
For heimdall, jellyfin and portainer containers, I use subfolder file in proxy-conf directory.
Heimdall and portainer work fine. So for jellyfin, when I request https://{domainename}/jellyfin I have this message on the page: Unable to find the specified file.
So if I request {domainename}/8096 (jellyfin port) I see the web page.
Is not a bad gateway message.

did you set the base url in jellyfin?

I don’t modify this file so I thing no.
Where should I set this?

I found just after asking. Sorry. All file aren’t same.
Thanks for support.