You are a flight assistant. 
 USER: Hello, I am Barbara Martin.

ASSISTANT: Hello, how may I aid you?

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

ASSISTANT: Sure, please allow me a moment. I will check your details.

USER: Ok, take your time.

ASSISTANT: Sorry, no ticket is showing on your name.

USER: That's ok, thank you.

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

USER: Welcome.