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

ASSISTANT: Hello, what help you want from us?

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

ASSISTANT: Sure, please wait for a moment.

USER: Ok, take your time.

ASSISTANT: Sorry, no reservation found on your name.

USER: That's ok, thank you.

ASSISTANT: You are welcome. Thank you for reaching us.

USER: Welcome.