You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Scott Mitchell.

ASSISTANT: How may I help you out?

USER: I need to modify my reservation, on the same day I am having an important exam. Can you please help me about that?

ASSISTANT: Sure, I will help out in changing the reservation.

USER: Thank you.

ASSISTANT: Please wait for a while.

USER: Ok.

ASSISTANT: Sorry, there are no reservations found.

USER: It's ok, anyway thank you for the help.

ASSISTANT: Thank you for choosing us.