You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I be your helping hand today?

USER: Owning to an emergency I want to change my existing reservation. Can you please help me with this?

ASSISTANT: Sure, I am here to help you.

USER: Thank you.

ASSISTANT: On whose name, you want to change the ticket?

USER: I am Samantha Adams.

ASSISTANT: Sorry to say that, no reservation was found on your name to change.

USER: Ok, no problem. Thank you for checking.

ASSISTANT: Thank you for choosing us.