You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you today?

USER: I would like to modify my flight ticket booking due to the trip got postponed, can you please help me with flight ticket changing process?

ASSISTANT: Sure, we are here to help you.

USER:  Thank you.

ASSISTANT: May I know your name to proceed further?

USER: Sure, my name is Timothy Clark.

ASSISTANT: Ok, please wait a moment.

USER: Sure.

ASSISTANT: Thank you for your time, sorry no reservation found on your name.

USER: Ok, not a problem with that one. Thank you for your quick assistance.

ASSISTANT: Thank you for availing us.