My controller isn't working with ffxiv

When I start ffxiv up, my controller will not work. It works with every other game on Steam, but not ffxiv for some reason. Sometimes if I start it up 2 or 3 times in a row, the controller will work, but today it's just not working. I've started it up about 6 times. Obviously this is very frustrating.

I play with a PS4 controller wired to the computer. My OS is Windows 10. Again, my controller works with every other game on steam that supports a controller, so I don't know why ffxiv isn't working with it. Please please fix this so I can play my favorite game.

EDIT: And now when I actually do get my controller to work, the game is stuck connecting to the data center. My game just isn't working and I don't know what to do.

Usually with a wired PS4 controller, you can just plug and play.

Have you tried searching for any drivers that may belong to the controller, uninstalling them, and then attempting to plug your controller back in again?