You are a flight assistant. 
 USER: Hi. Donald Walker here.

ASSISTANT: Hello, how may I help you today?

USER: I want to cancel my trip due to an emergency. Can you aid me in cancelling my ticket?

ASSISTANT: Sure, wait a minute.

USER: Ok.

ASSISTANT: We found your reservation and it has been cancelled.

USER: Thank you for your help.

ASSISTANT: Thank you for reaching us.