Before changing flights, check your eligibility. All of your options for changing a flight will be listed in the ticket's fare conditions. You can change or cancel a flight under the JetBlue flight cancellation policy if your flight was booked in the past 24 hours and is not less than 7 days away from the time of booking. A step-by-step guide to changing JetBlue flights is provided here.

https://www.flightslineup.com/....blog/jetblue-change-