You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I support you?

USER: I want to change my existing reservation due to my health issues, can you please help me with this?

ASSISTANT: Sure, please let me know your name.

USER: I am James King.

ASSISTANT: Ok, please wait.

USER: Ok.

ASSISTANT: Thanks for waiting, there is no reservation found by your name in our data base.

USER: It's ok, no problem. Thank you.

ASSISTANT: Thank you for choosing us.