You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

USER: I have planned an event with my friends but unfortunately it got postponed so please help me with changing my reservation.

ASSISTANT: Sure, I will help you in changing reservation. May I know your name please?

USER: Thank you. Sure, myself Robert Thompson.

ASSISTANT: OK, please wait a moment.

USER: Sure, take your time to check.

ASSISTANT: Sorry, there are no reservations found.

USER: Oh! May be booking has not done properly.

ASSISTANT: Thank you for reaching us.

USER: Anyway, thank you for your time.