You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: My grand father got some health issues and he is in hospital now, so I want to change my existing reservation. Can you please help me with that?

ASSISTANT: Sure, May I know your name?

USER: Sure, I am Helen Hernandez.

ASSISTANT: Sorry to tell that there is no reservation on your name.

USER: Ok, no problem.

ASSISTANT: Thank you for approaching us.

USER: Thank you for helping me.