Tunnel Connection Failed error when accessing WP site from external network

I have a LAMP server setup at home with wordpress. Static IP on the server and port 80 forwarded on the router to that server. Apache listening on port 80 and virtual host configured accordingly.

It was working fine but now when I browse to my domain gws.voyez.ca (that points to my public IP) browser just shows “Tunnel Connection Failed”. Oddly enough, I can still access pages in that folder (eg. gws.voyez.ca/test.html or gws.voyez.ca/phpinfo.php serve fine). This only happens externally; on internal LAN no issues. Have tried from multiple devices and different browsers.

It was working fine for a few weeks and just seems to have broken (no changes that I can think of).

Potentially ISP blocking something?

Thanks for reading.