You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I assist you?

USER: My name is Nicole Williams.

ASSISTANT: May I know your preferred travel dates to check the travel flight availability?

USER: Due to heavy work, I would like to postpone my holiday trip. Please change my existing reservation.

ASSISTANT: Ok, I will change the reservation. Sorry, there are no reservation been done on your name.

USER: Its ok, thank you for the information.

ASSISTANT: Thank you for connecting our agency.