You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you today?

USER: Due to some health issue, I want to change my existing reservation. Can you please help me with this?

ASSISTANT: Sure, can I know your name?

USER: I am Benjamin Campbell.

ASSISTANT: Ok, please wait.

USER: Sure.

ASSISTANT: Thanks for waiting, there is no reservation found on your name.

USER: Ok, Thank you.

ASSISTANT: Thank you for reaching us.