You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I guide you today?

USER: I am trying to change my existing reservation because the planned trip got cancelled suddenly due to some financial issues in the family. Can you please help me in changing the ticket?

ASSISTANT: Sure, I am glad to help you with that.

USER: Thank you.

ASSISTANT: Can I know your name to check your previous reservation?

USER: Yes, I am Christopher Thompson here.

ASSISTANT: Please wait a moment to check.

USER: Sure.

ASSISTANT: We regret to inform you that there is no reservation found on your name in our records.

USER: That's fine, no problem.

ASSISTANT: Thank you for reaching us, hope you have a great day.

USER: Anyway's thank you for your time.