You might need to delete/move your Final Fantasy XIV folder(C: -> Users -> YOURWINDOWSNAME -> Documents -> MyGames), it's well documented in other forums. Sometimes there is a complication with OneDrive where you have to disable the "Save space" option within OneDrive. Simply moving the Folder and its contents to the desktop should suffice as a test. Using this method will cause you to lose your settings so be prepared to redo many things if have not backed up your character data recently (ALWAYS BACK UP).

Good Luck!

PS: Reinstalling the game does NOT delete this folder necessarily, which is why the issue can persist past a reinstall. When reinstalling the game for issues such as this, always get a new version of the launcher and make sure you have either moved these config files, or deleted them if you are not concerned about losing your character settings locally.