You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: I want to change my travel dates, due to some problems I am unable to travel those dates so can you please change my reservation?

ASSISTANT: Sure, wait a while.

USER: Ok.

ASSISTANT: There is no reservation on your name in our database. May I know your name please?

USER: Oh! May be I am not booked my ticket properly at that time. Sure, my name is Andrew Walker. Thank you for your information.

ASSISTANT: Thank you for opting us.