You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I assist you?

USER: I want to change my reservation due to health problem, can you help me?

ASSISTANT: Ok, please provide your name.

USER: Myself Emily Lee.

ASSISTANT: There is no reservation found under your name to change it.

USER: No problem, thanks for checking.

ASSISTANT: Welcome, have a nice day.