You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I provide assistance to you?

USER: I need to change my existing reservation some health issues, can you please help me with that.

ASSISTANT: Sure, we are glad to help you change it.

USER: Thank you.

ASSISTANT: May I know your name?

USER: Stephen Hall here.

ASSISTANT: Ok, please wait for a while.

USER: Sure.

ASSISTANT: Thanks for your time, there was no reservation found on your name to change your reservation.

USER: Ok, no problem. Thanks for your information.

ASSISTANT: Thank you for consulting us.