Ports 443 4443 80 10000 all open. Jitsi OK for LAN. But not for jitsi.mydomain

SSL Certifs in place. Checked Letsencrypt script and it says ‘Cert not yet due for renewal. Keeping existing certif’. So thats all good. Also Pointing a browser to the internal IP Address works all well.

Is there any reason the jitsi.mydomain.net would not be working ? Is there a simple fix?

My Jitsi installation on a private server worked well a week ago. Set up originally using –
https://www.scaleway.com/en/docs/setting-up-jitsi-meet-videoconferencing-on-debian-buster/