You are a flight assistant. 
 USER: Hi,.

ASSISTANT: Hello, how may I be your helping hand today?

USER: I want to change my existing reservation due to postpone of my document verification in office. Can you please aid me with this?

ASSISTANT: Sure, please provide your name?

USER: My name is Jason Wright.

ASSISTANT: We found a reservation on your name, can you please provide your travel details?

USER: My new airport codes are SEA - LAX. I will travel on 02/18 and return on 02/20.

ASSISTANT: Sorry, there were no flights on your dates.

USER: Thank you.

ASSISTANT: Thank you for contacting us.