You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am David Perez.

ASSISTANT: David, how may I help you?

USER: Can you please help me in cancelling my recent reservation?

ASSISTANT: Sure, please give me a moment to check your ticket status.

USER: Ok, sure.

ASSISTANT: Sorry, no reservation is available on your route.

USER: Ok, fine thank you for checking.

ASSISTANT: Thank you for choosing us.