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

ASSISTANT: Hello, how may I aid you?

USER: Due to an emergency, I would like to change my reservation.

ASSISTANT: Sure. Let me check in our records.

USER: Ok, take your time.

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

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

ASSISTANT: Welcome. Thank you for reaching us.

USER: Welcome.