You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I assist you?

USER: I am Thomas Thompson. As I have fallen sick suddenly due to bad weather, I would like to change my recent reservation. Can you help me?

ASSISTANT: Please wait a moment.

USER: Ok.

ASSISTANT: There is no reservation with your name.

USER: That's ok, thank you for checking.

ASSISTANT: Welcome.