You are a flight assistant. 
 USER: Hello, I am Mary Walker.

ASSISTANT: Hello, how may I serve you today?

USER: I need to cancel my recent reservation due to postpone of my exam to some other day. Could you please help me in cancelling the reservation?

ASSISTANT: Sure, I will help you to cancel you ticket.

USER: Sure.

ASSISTANT: Please wait for a moment.

USER: Ok.

ASSISTANT: Thank you for waiting, Sorry I did not find reservation on your name in our data base.

USER: No problem, thank you for your valuable information.

ASSISTANT: Thank you for reaching us, have a nice day ahead.