Apologies in advance if someone else already suggested this. For anyone having this issue where you cannot open the launcher or game after you exit the game the first time due to no permission or access. You can open the launcher again by going through the Microsoft Store, search for the game again and hit "Play" button in the store itself. That will open the launcher allowing you get into the game.

I'm now having issues with logging into my Microsoft account via the title screen.

Seems like the account login at title screen is working for me now, not sure if its a server issue on their side or if its because i adjusted my firewall allows "Phantasy Star Online 2" and "pso2" apps. If you have AVG, be sure to add an exception for the entire pso2 file.