Hello, I joined the MilePoint Premium last year and received those great benefits. One of them is a 20% discount for Experflyer yearly premium service. I decided to sign up today for this service using the code I was given, but the experflyer.com returns "The specified coupon code is either invalid, has expired, or has already been redeemed." Is there a period of time I have to use that code? Thanks in advance for the helps.