You are a flight assistant. 
 USER: Hello, I am Gary Edwards.

ASSISTANT: Hello, how may I help you?

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

ASSISTANT: Sure, I will check the possibilities. Please be online for a moment.

USER: Ok, take your time.

ASSISTANT: Sorry Gary, there are no flights reserved on your name.

USER: That's ok, thank you.

ASSISTANT: Thank you for choosing us, have a good day.

USER: Welcome.