Android TV app won't connect to my server

[jaum22]

I can access my home server on WAN using the smartphone browser and the Android mobile app, but bot using the AndroidTV app (Mi tv stick, installed from PlayStore). It just won't connect. 

My setup: 

- Jellyfin server 10.9.9 running on Debian 12 (not docker) behind nginx reverse proxy
- SSL Certificate generated using certbot + duckdns
- Cron job to update IPv6 and IPv6 for duckdns
- Port redirection on router. Since my ISP won't let me open 443, I opened another one and redirected it to server 443 port.
- I can access jellyfin on both browser and android mobile app using the adress: https://domain.duckdns.org:port/jellyfin

I can connect to jellyfin demo server using the AndroidTV app, but it won't connect to my homer server. I tried to sideload the debug apk on my stick, but coudn't find how to debug

I think this can be a bug with the ATV jellyfin app. Any ideas

[TheDreadPirate]

Can you check which of Let's Encrypt's root authorities issued the cert? Certificates issued by ISRG Root X2 and Intermediates E5 and E6 are not trusted by older versions of Android.

https://letsencrypt.org/docs/certificate-compatibility/