Join Date: Jul 2003
Location: CGK
Programs: SQ TPP30, CX DM, DL P, FB P, AA G, GA CB, WOH LGLOB, HH D, MB G, Hertz P
Posts: 2,887
Usually, airlines charge you the more expensive return price of the two cities, if you are flying the same airline.
For example, SIN-JFK/LAX-SIN: SQ would charge the price of SIN-JFK-SIN for the ticket.
Have you tried e-mailling zuji customer service?