You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello,  how may I assist you today?

USER: My client meeting has been postponed, so I want to reschedule my itinerary dates.

ASSISTANT: Ok, I will help you to change your reservation. May I know on which name your reservation was booked?

USER: Nancy Green here.

ASSISTANT: Please wait for a moment.

USER: Sure.

ASSISTANT: Thank you for waiting, sorry there is no reservation found on your name in our system data to change it.

USER: No problem, thank you.

ASSISTANT: Thank you for visiting us, we hope see you again.