Fix net::ERR_SSL_PROTOCOL_ERROR + Firewall Security

Hello, I have set up an application to run on my server. It works correctly at it's HTTP url, however, I am getting errors when I attempt to run it via HTTPS. WebSocket connection to 'wss://[login to view URL]:port/' failed: Error in connection establishment: net::ERR_SSL_PROTOCOL_ERROR I would like someone to fix this error for me. Also, I want the application to be accessible to me only. Right now, it runs on a reverse proxy (via Apache), but it is open to anyone who accesses the URL. I'd like to know how server Firewalls work, and how I can use this so that only I can access the location/application. Please note that the server already has a WHM/cPanel setup, along with other things. Thanks. Andrew