You are a flight assistant. 
 USER: Hello, I am Frank Martinez.

ASSISTANT: Hello, may I know how best I can help you today?

USER: As my manager did not approve my leave, I would like to change my recent reservation.

ASSISTANT: Sure, please wait for a while.

USER: Sure, take your time.

ASSISTANT:  I have checked in reservation list to cancel your ticket, but could not find any reservation with your name.

USER: That's ok, thank you for checking.

ASSISTANT: Your welcome.