You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you today?

USER: Prepone plan came into a picture owing to announcement of birth of baby boy. Can you please help me change an existing reservation?

ASSISTANT: Sure, will you provide the name for checking the reservation?

USER: My name is Emily Gonzalez.

ASSISTANT: Your reservation is found. Will you provide your airport codes please?

USER: My airport codes are from AZ-PHX to NY-LGA.

ASSISTANT: Please provide your travelling dates that you want to travel.

USER: My travelling dates are from 12/21 to 12/23.

ASSISTANT: Please give me a moment.

USER: Sure.

ASSISTANT: There is no flights found under your details.

USER: That's not a problem. Thank you.

ASSISTANT: Thank you for reaching us, have a great day.