You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I aid you today?

USER: Myself Joshua Campbell. For some issues I want to change my reservation, can you please help me?

ASSISTANT: Ok, please give me a moment to check with your existing reservation.

USER: Ok.

ASSISTANT: Reservation found, what can I do now? Please share your travelling dates for new journey?

USER: Ok, my new travelling dates are from 06/28 and 06/30.

ASSISTANT: May I know your airport codes for this journey?

USER: I want to travel from JFK to EWR locations.

ASSISTANT: Joshua Campbell, no flights are currently available for you.

USER: It's ok.

ASSISTANT: Thank you for reaching us.

USER: Thank you for the information.

ASSISTANT: Have a great day.