sounds like something went haywire somewhere in the routing and/or security--your network session is basically failing. The fact you connected successfully via VPN points towards problems in route, but if that is no longer working then it may be something along the lines of security causing issues (something may have updated in the background and is now causing problems).

Make sure your security isn't interfering (check/add/update exceptions for the game's folders and/or it's executable files--or you can try disabling it briefly as well), and if it still persists you may need to get your route analyzed (tracerts/pings, other similar tools--your ISP should be able to do this if you aren't comfortable with it). Also make sure TLS support is enabled for the Internet Options at the OS level (run inetcpl.cpl from the run/search box, go to the Advanced tab and scroll down to the section about SSL encryption and make sure all the TLS options are enabled).

If you don't know the IP the client actually uses (the ones at ARRStatus haven't been reliable for a while now), you can use the lobby service addresses for testing route stability:

Canada:
neolobby02.ffxiv.com
neolobby04.ffxiv.com
neolobby06.ffxiv.com

Japan:
neolobby01.ffxiv.com
neolobby03.ffxiv.com
neolobby05.ffxiv.com

***note that the client also connects to servers in Japan periodically for authentication and such, so it may be worth checking the route to the Japan side as well.