First, I received an email from Singapore that they were unable to check me in at the 48 hour mark due to the lack of an ESTA. Yet in my membership information is my citizenship and my passport information. I logged in on my computer and tried 2 times to go thru check in with no success. At this point, I ended my efforts and will check in at the airport. I generally fly Singapore once a year and this is a new experience for me.