You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may i serve you today?

USER: I am David Martinez. Owing to an emergency, I want to cancel my ticket. Will you help me in that cancellation?

ASSISTANT: Sure,please wait for a minute I will get back to you.

USER: Ok.

ASSISTANT: Thanks for waiting, we found a reservation on your name, would you like me to cancel?

USER: Yes, cancel my ticket.

ASSISTANT: Ok, your reservation has been cancelled.

USER: Thank you.

ASSISTANT: Thanks for choosing us.