Fix SSL Error on IIS

I need help fixing an SSL error on my IIS server. Currently, when I try to access my website via HTTPS, it doesn't load and shows a "Secure connection failed" or an SSL handshake error.
Also, server is behind a cable router with the definition for port forwarding. Also the dns resolves the web site but it stops at the cable router. hen using the IP http ip address is passes through.

Requirements:
- Expertise in IIS and SSL configuration
- Experience troubleshooting SSL handshake errors
- Ability to diagnose and resolve HTTPS connection issues

Please include relevant experience in your bids.