You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. What would you like me to do?

USER: I am David Allen. Actually I want to cancel my recent reservation, due to some problems. Can you help me out?

ASSISTANT: Yes, sure I will cancel it for you.

USER: Ok.

ASSISTANT: David Allen there is no flight on your name.

USER: That's fine.

ASSISTANT: Thank you for choosing our service.

USER: Thank you for your help.