Need help with SSL

I’m trying to setup nextcloud with docker and synology.

I’ve my custom domain defined, routed and everything works as expected so far. I can go to my from within and external network, but I’m seeing “Not secure” warning. My domain points to my public IP address and ports 80 and 443 are forwarded to Synology in my router.

I tried creating SSL in docker GUI with Let’s Encrypt and did what this post says


In Synology DSM → Security → Certificate → Created Certificate → configure → I see my domain and is configured to certificate. But I’m still seeing the warning.

P.S I’m a beginner with servers, network interfaces and SSL certificates

Thanks in advance.