Is infant air ticket free of charge? I'm bringing my 6-month old baby but when i checked the ticket price, she's being charged. Also, do i have to request for bassinet if i'm taking SQ? Is there additional charge for a bassinet? If there is no bassinet available, does it mean baby will be on my lap? Thanks!

I don't think infant tickets are FOC. It would usually be heavily discounted but definitely not FOC. Also, even if it is FOC, think the airport taxes and surcharges will still apply. As for the bassinets, yes you would need to request beforehand because there is a limited number of bassinets onboard. If there is no bassinet, your child will be given an infant seatbelt. Bassinets are not to be used during takeoff, landing and during turbulence anyways. Here's some useful FAQs from the SQ website. You should call their friendly hotline, they are always so helpful when I have any enquiries: https://www.singaporeair.com/en_UK/us/travel-info/special-assistance/travelling-with-children/