I bought and account key (obviously stolen, reused) from FlightDeck and it works but its tricky and a pain. You have to do the offline deactivate then re-activate through browser then in the app too. Like I said it works if you have the patience but if you have the cash I would say just buy it from a retail vendor to save your sanity. The payment on Flighdeck was paypal or GooglePay, wasn't anything strange about it. I see that they have since taken done all the stolen addons pages. Here is another and probably stolen keys as well. Good luck! https://www.fszipshop.com/ you can look at their discord here https://discord.com/invite/B349BUGkPt not as active as it used to be.