You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I support you?

USER: I am Daniel Brown. Could you please change my existing reservation due to my health issue?

ASSISTANT: Sure, please give me a minute.

USER: Sure.

ASSISTANT: Thanks for your valuable time. There is no reservation available on your name.

USER: Not a problem, thank you for the information.

ASSISTANT: Thanks for availing us.