First time doing this, Tues-Tues travel various days work, can't seem to get it to work on other days. Confirmed booked through WebJet. JetBlue codeshare flight on SQ LAX-NRT-SIN

Fare Basis Code : JNX0Z7SP

OR JNX0Z7SP TYPE FARES

CHANGES/CANCELLATIONS

BEFORE DEPARTURE
CHANGES/CANCELLATIONS PERMITTED.
NOTE -
RESERVATIONS MADE ONE WEEK OR MORE PRIOR TO A FLIG
HTS SCHEDULED DEPARTURE MAY BE CANCELED WITHOUT PE
NALTY UP TO 24 HOURS AFTER THE RESERVATION IS MADE
.
RESERVATIONS MADE ON JETBLUE.COM THRU JETBLUE
RESERVATIONS OR BY AN AGENCY THRU GDS MAY BE
CHANGED OR CXLD FOR A FULL REFUND WITHOUT THE
CHANGE/CXL FEE PRIOR TO SCHEDULED DEPARTURE.
CHANGES IN ITINERARY WHICH RESULT IN A DECREASE IN
FARE WILL BE REFUNDED TO ORIGINAL FORM OF PAYMENT
AND ANY INCREASE IN FARE MUST BE COLLECTED AT TIME
OF TICKET EXCHANGE.
REFUNDS ON REFUNDABLE TICKETS MUST BE PROCESSED
BACK TO THE ORIGINAL FORM OF PAYMENT BY THE AGENCY
THAT ISSUED THE TICKET. IF PAYMENT OR PARTIAL
PAYMENT WAS MADE USING A CREDIT CARD THE REFUND
MUST BE PROCESSED BACK TO THE SAME CREDIT CARD. IF
PAYMENT OR PARTIAL PAYMENT WAS MADE USING TRAVEL
BANK FUNDS/CREDITS THE REFUND MUST BE PROCESSED
BACK TO THE CUSTOMERS TRAVEL BANK ACCOUNT. IF
PAYMENT OR PARTIAL PAYMENT WAS MADE USING AN MCO
THE REFUND MUST BE PROCESSED BACK TO A NEW MCO. IF
PAYMENT OR PARTIAL PAYMENT WAS MADE USING CASH OR
CHECK THE REFUND MUST BE PROCESSED BACK TO THE
CUSTOMER IN THE FORM OF CASH OR CHECK.

AFTER DEPARTURE
CHANGES/CANCELLATIONS PERMITTED.
NOTE -
RESERVATIONS MADE ON JETBLUE.COM OR THRU JETBLUE
RESERVATIONS THAT ARE NOT CHANGED OR CXLD PRIOR TO
SCHEDULED DEPARTURE WILL NOT BE REFUNDED BUT WILL
BE PLACED IN THE CUSTOMERS TRAVEL BANK ACCOUNT AS
A CREDIT FOR USE ON FUTURE TRAVEL. TRAVEL BANK
FUNDS/CREDITS ARE VALID FOR 1 YEAR FROM THE DATE
OF ISSUANCE AND ARE ONLY VALID FOR DIRECT BOOKINGS
WITH JETBLUE.
RESERVATIONS MADE BY AN AGENCY THRU THE GDS THAT
ARE NOT CHANGED OR CXLD PRIOR TO SCHEDULED
DEPARTURE WILL NOT BE REFUNDED BUT THE TICKET WILL
REMAIN IN OPEN STATUS FOR 1 YEAR FROM THE DATE OF
ISSUANCE AND MUST BE USED BY THE ORIGINAL
PASSENGER. THE AGENCY CAN ALSO REFUND THE VALUE OF
THE TICKET TO AN MCO FOR USE ON FUTURE TRAVEL AND
THE MCO IS FULLY TRANSFERABLE.

NOTE -
ALL NEW BOOKINGS ARE SUBJECT TO APPLICABLE FARE
RULES. PASSENGER MUST BE PRESENT IN BOARDING AREA
TEN-10-MINUTES PRIOR TO SCHEDULED DEPARTURE TIME
OR POSTED AIRCRAFT DEPARTURE TIME OR IT MAY RESULT
IN THE CANCELLATION OF THE PASSENGERS RESERVATION
AND FORFEITURE OF ANY PAYMENT.

Hope this applies as a good deal...