I booked with cebu pacific online three months ago with my singapore issued citibank and it went through.Last month, i book another but it keeps on rejecting my card, I called them, and was told that theyre working on it.2 weeks ago, I tried again, and it goes well.
I had my friends in US buy tickets online using their American issued cc,its now working..
Try this time, apparantly they solved the glitch.
If u dont have patience, book somewere else.