You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: I am Scott Robinson.

ASSISTANT: How may I help you out?

USER: I want to change my existing reservation due to postpone of my board meeting, so can you please help me in changing my reservation?

ASSISTANT: Sure, I will help you in changing the ticket.

USER: Thank you.

ASSISTANT: Sorry, there are no reservations found.

USER: Not a problem, thank you for checking.

ASSISTANT: Thank you for reaching us.