I have the same problem, but is just with this game, i don't have any problem paying in othes games, is just with this one that a error message appears saying "Payment method not available at this time" So i guess the problem is this page specifically(?
Its because of Stripe! Stripe only has 46 countries available, and the rest 149 of the countries cannot use it. Unfortunately, I belong to one of those 149 countries, and so I can't do anything about it :(
