You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, do you need any assistance from us?

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

ASSISTANT: Sure, I am delighted to help you. Can you please tell me your name?

USER: Myself Edward Wilson.

ASSISTANT: Sorry, there is no reservation with your name to change further.

USER: No problem, thanks for checking.

ASSISTANT: Thank you for choosing us.